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Asymmetric Synthesis of Quaternary Hydantoins via a Palladium-Catalyzed Aza-Heck Cyclization
No full textThis article was originally published in Journal of the American Chemical Society . The version of record is available at: https://pubs.acs.org/doi/10.1021/jacs.5c16022
This publication is licensed under CC-BY 4.0 https://creativecommons.org/licenses/by/4.0/
© 2025 The Authors. Published by American Chemical SocietyAn asymmetric, palladium-catalyzed aza-Heck cyclization to prepare enantioenriched 5,5-disubstituted hydantoins (quaternary hydantoins), which are medicinally important compounds but are classically challenging to prepare, is reported. The required substrates can be prepared readily from α,β-unsaturated amides in a single operation, and aza-Heck cyclization provides a wide range of topologically complex, highly substituted, pharmaceutically relevant hydantoins. The capacity of this method to impact the synthesis of drug substances is demonstrated by the first asymmetric synthesis of the anticonvulsant (R)-mephenytoin.We are grateful to the University of Delaware (UD) and the NIH (R01GM145617) for their support. EAM was supported by a UD Graduate Scholars Award and UD Chemical and Biology Interface Program (NIH T32-GM133395). We are also thankful for the UD High-Throughput Experimentation and Chromatography (HiTEC) Lab and Dr. Jessica Sampson for help. Data was acquired at UD on instruments obtained with the assistance of the NSF, NIH, and the Unidel Foundation (NSF CHE0421224, CHE0840401, CHE2404894; NIH R01GM102358, R01GM111820, S10RR026962, S10OD016267, S10OD025185, P20GM156674, P20GM104316, and P30GM110758; Unidel-18D)
Physics-based and data-driven in-silico methods for the inverse design of nano and polymeric materials
No full textJayaraman, ArthiThe rational design of novel high-performance materials is imperative to sustainably addressing the unprecedented challenges such as climate change, increasing energy demands, and pollution that are associated with anthropogenic activities. The design of novel materials has traditionally relied on the forward design process, a trial-and-error based approach where candidates are systematically synthesized, characterized, and finally benchmarked for its targeted application. The sequential forward design process is conceptually straightforward and has driven many major scientific discoveries over the years; however, this empirical methodology is inefficient as it is both time-consuming and resource-intensive due to the vast size of the chemical space. Despite advances in automated high-throughput experimental techniques that improve design space exploration rates by multiple orders-of-magnitude, this naïve brute-force approach has motivated the development of inverse design approaches to guide rational design. Inverse design involves starting with a target material property and searching for designs that meet the specified criteria. Techniques that can intelligently and efficiently navigate high-dimensional design spaces is required to address the intrinsic challenges that plague inverse design problems; they often are ill-posed (or weakly conditioned) and may not have unique solutions. ☐ In this thesis, I focus on developing novel physics-based and data-driven in-silico methodologies to solve inverse design problems for engineering novel materials (catalysts and polymeric materials) to drive high-throughput experimentation. I combine first-principles calculations with modern computing and statistical techniques such as Bayesian Inference, Bayesian Optimization, and machine learning to address two separate thrusts: (1) in-silico driven spectroscopic analysis of material structure and (2) efficient inverse design of high-performance materials. ☐ In Chapter 2, I combine data-based approaches with physics-driven surrogate models to develop a high-throughput methodology to predict catalyst structure directly from adsorbate infrared spectroscopy for supported subnanometer clusters. In Chapter 3, I present a novel plasma-driven methodology for synthesizing shape-controlled nano-catalysts and develop a computational methodology for identifying and monitoring structure during the synthesis procedure directly from adsorbate infrared spectroscopy and X-ray photoelectron spectroscopy. In Chapter 4, I study the fluxional nature of supported catalysts due to temperature directly from X-ray spectroscopy and elucidate structural changes using computational methods to help design efficient catalysts for structure-dependent chemistries. In Chapter 5, I present a novel molecular dynamics driven methodology called Rapid Analysis of Polymer Structure and Inverse Design strategY (RAPSIDY) to drive high-throughput screening of block copolymer stability with multiscale structures and accelerate screening over traditional computational methods by 2-orders-of-magnitude. In Chapter 6, I present a new version to RAPSIDY, RAPSIDY 2.0, to drive inverse design of high-performance block copolymers that exhibit desired macroscale material properties (e.g., tensile strength and thermal conductivity) using a combination of molecular dynamics and Bayesian optimization-driven active learning. Finally, in Chapter 7, I present the conclusions and summaries of the works in this dissertation and discuss future research directions.University of Delaware, Department of Chemical and Biomolecular EngineeringPh.D
Bahraini residents' views on Sustainable Smart City implementation and societal shifts in Manama: a pilot study
No full textYanich, DaniloAs the Kingdom of Bahrain increasingly adopts Sustainable Smart City (SSC) frameworks, questions arise about the impact of these models on the social fabric of the urban core in its capital, Manama. SSC frameworks integrate Information and Communication Technology (ICT) with urban planning to promote smart solutions and sustainable development. Manama’s evolution – from pre-oil Islamic-based city planning models to maritime trade towns and post-oil business districts – has rendered it an adaptable, dynamic city and a desirable site for SSC integration. However, as a melting pot of cultures and backgrounds, the city’s modernization process could significantly impact its social and cultural cohesion. Given the limited studies examining Bahraini residents’ perceptions of SSC planning an integration in Manama, this study seeks to answer the following research question: How do residents in Bahrain perceive the impact of sustainable smart city implementations and modernization on cultural and social connections in Manama during the period of January–February 2025? The research uses a cross-sectional and exploratory design to investigate potential correlations between demographic factors – such as gender, education, homeownership, ethnicity, governorate of resident and duration of residence in Manama- and perceptions of cultural significant, modernization, and SSC applications in the city. A Chi-square test was employed to examine potential relationships between independent and dependent variables and to identify statistically significant relationships. Findings reveal that residents from different governorates exhibit varying levels of familiarity with SSC initiatives. Income levels, age groups, and gender also influence perceptions, with some groups expressing heightened concern over privacy breaches and socioeconomic disparities that may arise through SSC integration in Manama. Therefore, this study addresses a research gap on different demographics in Bahrain and their perceptions on different SSC components integration in Manama.University of Delaware, School of Public Policy and AdministrationM.A
Enhancing delamination detection and monitoring of concrete bridges through infrared thermography, deep learning, field data, and numerical simulations
No full text"At the request of the author or degree granting institution, this graduate work is not available to view or purchase until April 10 2026"--ProQuest citation/abstract page."Na, RiConcrete bridges are essential for a safe, efficient transportation infrastructure, yet they are vulnerable to deterioration over time. One of the most critical forms of damage is delamination, in which layers of concrete separate due to corrosion of the embedded steel reinforcement. Traditional detection methods, such as hammer-sounding or chain-dragging, are time-consuming, subjective, and error-prone. In response, this dissertation proposes a multi-faceted strategy that combines infrared thermography (IRT), deep learning, field data, numerical simulations, and augmented reality (AR) to achieve faster, more reliable, and more objective delamination detection and maintenance planning. ☐ The study begins by collecting both field data and numerically simulated images under varied geometries, environmental conditions, delamination properties, locations, image processing techniques, and augmentation approaches. This extensive dataset serves to build a robust object detection–based deep learning model that removes the need for subjective external inputs—a key limitation of many earlier image segmentation techniques. The models evaluated here, Mask R-CNN and YOLOv5, benefit from the inclusion of simulation-generated images, thereby overcoming significant obstacles in the literature related to limited training data, minimal exploration of deep learning methods for IRT-based delamination detection, and incomplete datasets that result in overfitted models resulting in missed or misclassified defects. ☐ These numerical simulations not only supply diverse training examples but also allow for an investigation into how different climate zones and seasonal changes across the United States affect optimal IRT inspection times. Many prior studies on ideal detection windows have been limited to isolated locations and times, leading to conflicting or incomplete conclusions due to the difficulty and impracticality of filed data collection. This research details optimal delamination detention conditions and timeframes by simulating and examining detection accuracy throughout the day and across multiple seasons. ☐ The final stage introduces an AR-integrated platform that displays, in real-time, the delamination regions revealed during the data analysis process. This tool enhances both collaboration and data management during inspections by integrating current findings with earlier inspection records and maintenance logs, generating a complete history of bridge health. ☐ In field trials on a custom-built mockup slab and an in-service bridge, supplementing real IRT data with simulation-based images significantly improved deep learning outcomes, enabling accurate delamination detection across several conditions, most notably deep delamination detection – a significant limitation of current NDE techniques. For diverse U.S. climate zones, midday to early evening emerged as a generally favorable window for inspection. The AR-based system successfully consolidates multiple nondestructive evaluation (NDE) results and historical data into a single, user-friendly interface, suggesting strong potential for streamlining bridge inspection and maintenance practices.University of Delaware, Department of Civil, Construction and Environmental EngineeringPh.D
Efficacy of Mobile Applications and Face-to-Face Social Interaction on Physical Activity, Motivation and Self-Efficacy in Insufficiently Active College Students
No full textThis article was originally published in [Journal Name]. The version of record is available at: https://doi.org/10.51137/wrp.ijdht.306
Copyright (c) 2025 Jung E. Lee, Mikayla McCullough, Yoonsin Oh, Daehyoung Lee (Author)
Creative Commons License
This work is licensed under a Creative Commons Attribution 4.0 International License. https://creativecommons.org/licenses/by/4.0/The purpose of this study was to examine the efficacy of mobile app-based intervention and face-to-face social interaction on physical activity and psychological outcomes in insufficiently active college students. Fourteen college students (Mage= 19.9, SD=1.1; 9 females) participated in a 4-week intervention using Samsung Health and Snapchat mobile applications, along with weekly in-person group meetings. Step counts were measured using Tri-Axis Pedometer (OMRON HJ-303), while exercise motivation and self-efficacy were assessed using Exercise Self-Regulation Questionnaire (SRQ-E) and 12-item abbreviated version of the Self-Efficacy for Exercise Habit Survey. Paired t-tests compared pre- and post- intervention outcomes. Results indicated significant improvements in introjected regulation, identified regulation, intrinsic motivation, and exercise self-efficacy. Average daily step counts increased from 5,839 to 6,610 steps, although this change was not statistically significant. These findings suggest that integrating mobile health apps with peer social support is feasible and may enhance exercise motivation and self-efficacy in insufficiently active college students. Fitness and health professionals may consider leveraging integrated online and offline interventions to optimize physical activity outcomes
Considerations for using sharks as ocean observing platforms
No full textThis article was originally published in ICES Journal of Marine Science Published by Oxford University Press. The version of record is available at: https://doi.org/10.1093/icesjms/fsaf011.
© The Author(s) 2025. Published by Oxford University Press on behalf of International Council for the Exploration of the Sea. 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 combination of animal-borne telemetry and oceanographic sensor technologies creates an opportunity for marine animals to serve as ocean observing platforms (OOPs), carrying tags that record in situ oceanographic data as they naturally move. In this study, we create a blueprint of shark OOP species selection, quantifying and comparing the potential for species to transmit collected data, the environmental ranges various candidates are expected to encounter, and the oceanographic features they may be expected to resolve. Metrics of data satellite transmission probability, movement behaviors, and environmental sampling ranges are calculated combining historically collected satellite tag data for 11 shark species tagged in the Atlantic and Pacific Ocean basins. Species with the highest satellite data transmission potential include shortfin mako (Atlantic and Pacific) and blue (Pacific) sharks. These species also demonstrated overlap in time and length scales for area-restricted search-like movement behaviors with several mesoscale ocean features, including hurricanes and upwelling events. Additional comparisons of decorrelation time scales between theoretical shark versus glider sampling platforms suggest that shark OOPs have the ability to provide three times more uncorrelated water column temperature and conductivity profiles than gliders at 15% of the operational cost.Funding for this study was provided by the National Oceanographic Partnership Program (NOAA Award—NA20NOS0120221)
Impact of heat stress on the post-hatch growth, morphometrics, and allometry ofthe chicken (Gallus gallus)
No full textThis article was originally published in British Poultry Science. The version of record is available at:https://doi.org/10.1080/00071668.2025.2542894
© 2025 The Author(s). Published by Informa UK Limited, trading as Taylor & Francis Group This is an Open Access article distributed under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits unrestricted use,distribution, and reproduction in any medium, provided the original work is properly cited. The terms on which this article has been published allow the posting of the Accepted Manuscript in a repository by the author(s) or with their consent1. Heat stress negatively affects animal growth. This study examined the impact of heat stress on a modern broiler (Ross 708) chicken compared to a heritage meat-type chicken line (UIUC).
2. To mimic the effects of a heat wave, birds were exposed to daily, cyclic high ambient temperatures between post-hatch d 21-42, while control birds were maintained at thermoneutral temperature throughout this period.
3. On d 28 and 42 post-hatch, eight heat-stressed and eight control birds from both lines were weighed, necropsied and total organ masses were determined for the brain, breast muscle, liver, small intestine, and spleen.
4. Normalised tissue mass at d 42 under thermoneutral conditions for the Ross 708 breast muscle was 2.4-fold larger than that of the UIUC chickens. The cross-sectional area of the Ross 708 breast muscle cells was also twofold larger than that of the UIUC birds. In contrast, UIUC birds had larger heart, spleen, duodenum, jejunum, ileum and brain masses than the Ross 708 chickens when raised at the thermoneutral temperature.
5. These results indicated that heat-stress shifted growth resources away from immune, skeletal muscle, neuronal and hepatic systems to maintain the heart and small intestine.This material is based upon work supported by the National Science Foundation under Grant No. 1147029 and by the Agriculture and Food Research Initiative Competitive Grant No. NIFA 2010-04233 from the USDA National Institute of Food and Agriculture
“FROM COP CITY TO PALESTINE”: DIGITAL PLACEMAKING AS TRANSNATIONAL SOLIDARITY
No full textenterThe Georgia International Law Enforcement Exchange (GILEE), a program
facilitating exchanges of policing techniques and technologies between the Atlanta
Police Department and the Israeli Defense Forces, has initiated the construction of a
militarized police training center called Cop City. The violent policing tactics Israel
weaponizes against Palestinians are now exported to the United States. Atlanta’s
activists in the Stop Cop City movement and Palestinians resisting occupation note the
formal connections between the two sites and employ digital placemaking tactics to
collaboratively contest dominant narratives of place. I argue that these transgressive
digital placemaking practices are a form of transnational solidarity, bringing together
geographically disparate actors in a common political struggle.ente
In vivo and ex vivo lentiviral and stem cell therapy approaches for progressive systemic skeletal dysplasia: mucopolysaccharidosis IVA
No full textTomatsu, ShunjiMucopolysaccharidosis IVA (MPS IVA) is caused by a mutation in the N-acetylgalactosamine-6-sulfate sulfatase (GALNS) gene, leading to glycosaminoglycan (GAG) accumulation in multiple tissues, resulting in progressive skeletal dysplasia and poor quality of life. There is no effective treatment for this skeletal disease at present. This study proposes an extensive evaluation of novel lentiviral (LV) and hematopoietic stem cell (HSC) gene therapy (GT) that produce and secrete the active GALNS enzyme at supraphysiologic levels within the cells. LVs carrying the native GALNS encoding sequence (cDNA) were made under three different promoters: CBh, COL2A1, and CD11b. Moreover, we designed LVs carrying the native GALNS cDNA tagged with D8 octapeptide under CD11b promoter and a human codon-optimized GALNS cDNA under CBh promoter, respectively. We first confirmed the potential impact of LVs in vitro and translated our research into an MPS IVA animal model. Translational research was performed under both ex vivo LV-mediated HSC transplantation into myeloablated recipient MPS IVA mice and in vivo direct infusion of LVs into bloodstream MPS IVA mice. Following tissue collections, enzyme activity, GAG levels, vector copy numbers (VCNs), histopathological evaluations, and bone morphometric analysis were performed at both cellular levels and in treated mice. LVs under the COL2A1 promoter produced the highest enzyme activity and normalized the storage materials in vitro, followed by the CBh promoter. Both LVs effectively modified donor MPS IVA HSCs that were further transplanted into busulfan-myeloablated MPS IVA recipients. This ex vivo LVGT, although the expression of hGALNS was lower, provided full correction of heart tissue and slight correction of bone pathology. We also investigated the potential effects of direct infusion of LVs. In this part of our research, we evaluated age-dependency (newborn vs. older mice), therapeutic doses (low-moderate-high doses), administration routes (intravenous, intramuscular, and intravenous), promoters (CBh, COL2A1, and CD11b) with high potential to drive gene expression in vivo and codon optimization of hGALNS enzyme in vivo. Our data confirmed the efficiency of systemic delivery rather than local administration under high doses of LVs into newborn MPS IVA mice. Parallel to in vitro and ex vivo assessment, we found that intravenous administration of LV-CBh or LV-COL2A1 viral vectors drove the hGALNS transgene expression at high levels. However, most LVs were integrated in the liver and the rest cleared from the body, which resulted in a slight correction of bone pathology. Local administrations, however, did not improve the course of disease biochemically or pathologically. Additionally, we noted an increase in anti-hGALNS antibodies, suggesting an immune response to the therapy. Overall, these findings of a broad range of therapeutic strategies evaluated here indicate that LVGT could be a promising approach for treating MPS IVA and similar skeletal disorders when combined into HSCs, offering hope for future advancements in the field.University of Delaware, Department of Biological SciencesPh.D