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Looking for Kevin: A Rereading of Rosaleen O’Toole’s Journey in Katherine Anne Porter’s “The Cracked Looking-Glass”
No full textThis is an Accepted Manuscript of an article published by Taylor & Francis in The Explicator on 01/13/2025, available at: https://doi.org/10.1080/00144940.2025.2451917.
© 2025 Taylor & Francis Group, LLC.
This article will be embargoed until 07/13/2026.In a 2024 interview, Darlene Harbour Unrue was asked what she discovered when researching Porter’s life for the 2005 biography that Joan Givner’s Citation1982 one had not unearthed. She replied, “well I found some extra husbands.” The additional two, albeit short-lived, marriages Unrue uncovered brings the total to five. Wed and divorced a whopping five times—no small feat, especially for a woman born in 1890—Porter unsurprisingly casts couples in troubled unions in a good bit of her fiction. One of her “strongest condemnations of romantic love,” as Mary Titus noted, is “The Cracked Looking-Glass,” a story that has not received nearly as much critical attention as Porter’s other works.Footnote1 The highly crafted, multi-layered tale drew inspiration from rumors Porter heard when summering in Merryall Valley, Connecticut, in 1926, about a rich Irish widow “who scandalized her rural neighbors by keeping young boys as boarders” (Unrue 138). When learning of these speculations, Porter herself was living with a man 11 years her junior—Ernest Stock, an English painter and former Royal Air Force pilot.Footnote2 Their relationship ended with the season. Unrue points out in her biography that Stock was but one in a “chain of liaisons with much younger men”—Eugene Dove Pressly, later Albert Erskine, among others (138). When “The Cracked Looking-Glass” was published, Porter had experienced firsthand the difficulties of being in a relationship with a significant age gap and yet she continued putting too much stock in affairs with younger men
Impact of hydrologic disturbances and water chemistry on soil biogeochemistry in an upland coastal forest
No full textVargas, RodrigoHydrologic disturbances driven by sea level rise and storm surges are altering biogeochemical processes in coastal forests, transforming upland ecosystems into wetlands. However, the effects of repeated flooding on belowground dynamics during the early stages of this transition are not well understood. This study investigates how repeated hydrologic disturbances with different water chemistries impact soil biogeochemistry dynamics in upland coastal forest soils. We conducted a mesocosm flow-through incubation experiment, applying freshwater (FW) and brackish water (BW) pulses to intact soil cores from a temperate coastal forest previously exposed to these treatments in separate field plots. Continuous measurements of CO2, CH4, and N2O fluxes were coupled with δ13C-CH4 isotopic analysis, porewater chemistry (DOC, SO42-, S2-, Fe2+, Mn2+, NH4+, NO3-+NO2-, ORP, pH), and Fourier-transform infrared spectroscopy (FTIR) of soil organic functional groups. Results showed that BW treatments resulted in stronger legacy effects, enhanced reducing conditions, increased CH₄ and N₂O fluxes, and alterations in soil organic matter. Elevated S2- and δ13C-CH4 signatures indicated the co-occurrence of sulfate reduction and methanogenesis via the methylotrophic pathway. Accumulation of NH4+ and N2O suggested potential dissimilatory nitrate reduction to ammonium (DNRA) and incomplete denitrification. Increases in Fe²⁺, Mn²⁺, and DOC indicated the destabilization of organo-mineral associations, while FTIR analysis revealed changes in soil functional groups, including degradation of polysaccharide structures and incorporation of sulfur- and nitrogen-containing groups. Our findings underscore the vulnerability of upland coastal forest soils to repeated inundation, revealing water chemistry–dependent responses and highlighting the complex biogeochemical feedbacks triggered by brackish water intrusion.University of Delaware, Department of Plant and Soil SciencesM.S
Measurement of hydrogen permeability and crossover in PEM electrolyzer membranes
No full textPrasad, Ajay K.Hydrogen production via proton exchange membrane (PEM) electrolyzers is an essential technology for the transition to sustainable and carbon-free energy systems, offering efficient and scalable solutions for green hydrogen generation. However, hydrogen crossover through the electrolyzer membrane remains a critical challenge, impacting system efficiency and safety. This thesis is focused on the measurement of hydrogen permeability of novel membrane materials designed to mitigate hydrogen crossover. The membranes were then installed in a single cell electrolyzer and hydrogen crossover was measured under unpressurized and pressurized conditions. ☐ The study is divided into three phases. The first phase involves characterizing the hydrogen permeability of candidate membranes using a depressurization cell setup, where temperature and hydration level are varied to assess the membrane’s hydrogen permeability under various operating conditions. In the second phase, the selected membranes were integrated into an unpressurized PEM electrolyzer and hydrogen crossover was monitored using a gas detector. In the final phase, the membranes were tested in a pressurized PEM electrolyzer at 10-30 bar to examine performance, operational stability and hydrogen crossover under pressurized conditions. ☐ The findings of this research offer valuable insights into advanced membrane materials with significantly reduced hydrogen crossover that can enhance the performance of PEM electrolyzers under both standard and pressurized conditions. This work contributes to the development of more efficient and scalable electrolyzers for large-scale hydrogen production, supporting the global transition to a robust hydrogen economy.University of Delaware, Department of Chemical and Biomolecular EngineeringM.Ch.E
Parsing pulses: testing the limits of temporal phase perception in human vision
No full textSchneider, Keith A.Complete information about temporal visual stimuli is available to human conscious awareness at frequencies below about 10 Hz, a threshold known as the Gestalt Flicker Frequency threshold. At faster frequencies, approximately 10–60 Hz, flicker is perceived but the accurate discrimination of temporal phase is not possible. Above about 60 Hz, the Critical Flicker Fusion frequency, stimuli are completely fused and not perceived as temporally varying. To accurately measure temporal phase limits, care must be taken to avoid activating low-level mechanisms that might invoke a perception of motion, which could bely temporal phase. This study explores the temporal properties and neural mechanisms underlying phase discrimination in human vision by examining the impact of interstimulus spacing and hemifield placement on temporal frequency thresholds in a paired achromatic flicker task. Experiment 1 was conducted with binocular viewing and found that narrow interstimulus spacing resulted in higher phase discrimination thresholds, suggesting contributions from low-level motion detection. Wide spacing relied on high-level processing, which led to reduced thresholds. Experiment 2 utilized dichoptic viewing to assess whether low-level motion detection occurs before binocular combination in V1, with findings showing reduced thresholds irrespective of spacing, suggesting that low-level mechanisms were successfully disabled with dichoptic viewing, and that discriminations were instead performed by high-level mechanisms in higher-order cortical areas. Despite the wide range of stimuli that jointly activate these mechanisms due to their overlapping temporal ranges, these results reveal that apparent motion and high-level processing appear to work independently. Once apparent motion is eliminated, thresholds drop to 7–10 Hz. ☐ Keywords: temporal phase discrimination; flicker fusion; psychophysics; visual perception; binocular vision; dichoptic vision; apparent motionUniversity of Delaware, Department of Psychological and Brain SciencesM.S
USING ASTEROSEISMOLOGY TO INVESTIGATE THE PULSATING HYDROGEN-RICH WHITE DWARFS HL TAU 76 AND EC14012-1446
No full textenterWhite dwarfs (WDs) are the final stage of stellar evolution for approximately
98% of stars, including the Sun. WD evolution is dominated by cooling. As they cool,
they pass through specific temperature ranges, or instability strips, where pulsations
are initiated. We are able to gain valuable insight into stellar parameters of these
fascinating objects using asteroseismology. Asteroseismology is the study of a star’s
internal structure through the analysis of its pulsations. In particular, it’s important to
study hydrogen-atmosphere white dwarfs (DAs), as they comprise approximately 80%
of the WD population. The pulsation behavior of these pulsating DA white dwarfs
(DAVs) has broader implications for our comprehension of stellar evolution and the
formation of white dwarfs, which play a vital role in the evolution of our Solar System
and of the Universe. In this work, we will present our findings on two DAVs, HL Tau
76 and EC 14012-1446. There is a significant amount of observational data for both
DAVs. This amassed data is a result of both ground-based telescopes and space-based
observations. The DAV population has similar physical properties, so the study of
these two DAVs allows for a more comprehensive understanding of the general DA
population. This is the first time a comprehensive analysis of these two stars has been
undertaken.ente
Sensitivity analyses and meta-modeling in complex decision support tools for transportation asset management
No full textMcNeil, SueThe importance of decision support tools in transportation asset management (TAM) cannot be over-emphasized. Decision support tools have been developed to solve a variety of TAM problems, yet Departments of Transportation (DOTs) also continue to develop new decision support models without necessarily measuring the perceived benefits from the new model viz-a-viz existing models. Furthermore, some studies, as well as interactions with practitioners, have shown that the agencies sometimes revert to simple, legacy tools due to the blackbox nature of newer, more complex models, as well as their analytical and computational requirements. Efforts should be made to encourage appropriate use of the available complex tools. ☐ This research involved two objectives. The first objective explored the role of verification and validation of decision models in TAM through variance-based sensitivity analysis techniques. The sensitivity analysis helps to understand how model parameters and variables influence policies and decision, thereby reducing the skepticism inherent in the use of complex models. The second objective proposed and implemented a meta-model framework as a higher-level tool to facilitate the matching of a set of decision support tools to appropriate decision contexts. ☐ In the first objective, a global sensitivity analysis technique, called Sobol’s method is used to identify the importance of the model’s input variables and parameters of a case-study complex decision support tool. The analysis showed that, unlike local methods, where the sensitivity of the model’s outcomes to the inputs are examined one at a time, the Sobol method showed a superior ability to identify the interactions among parameters and their importance. That is, the analysis showed that one must be careful in dealing with the parameters in complex decision support tools as there is a tendency to erroneously underestimate the influence of some parameters on the output when they are considered independently as opposed to their combined effects which may reveal that they are otherwise consequential to the outcome of the model. ☐ In the second objective, a machine-learning-based meta-model procedure for selecting appropriate support tools for specific decisions according to the scenarios encountered was demonstrated. Three case study decision support tools were applied to different decision scenarios that are characterized by the transportation network variables. A model assignment rule for selecting the most appropriate tool for each scenario was defined using the differences in the outputs from the different tools. This produced a labeled dataset for each decision scenario. A chi-square test performed on this data revealed a significant association between the congestion levels on the networks and the choice of decision thereby reinforcing a hypothesis that the complex tool may be favored in congested networks. A cluster analysis indicated that two of the three models were dominantly favored in all the clusters identified, suggesting that the asset manager may focus less on the third model. The labels of the scenarios were reassigned disregarding the least dominant model and a classification model was trained to predict the appropriate tool to use for future scenarios. Five classification algorithms, logistic regression, support vector machine, k nearest neighbor, decision trees and random forest, were trained. Principal component analysis was to reduce the dimensionality of the data and the principal components were used as the independent variables. The findings show that it is possible to reduce the catalog of decision support tools available to solve the same problem by identifying the ones that will not apply to a group of scenarios with similar characteristics. The performance of the meta-model classifier also shows that the proposed framework can predict the most preferred decision support tools to use for previously unseen scenarios. ☐ In summary, complex decision support tools have their place in TAM. However, their use is not always warranted. Furthermore, users of such models should conduct rigorous local and global sensitivity analysis to verify that the models behave as expected and to assist in parameter selection. This research demonstrated the value of such rigorous sensitivity analysis and the meta-model framework in the context of three decision tools and a selection of toy networks. Additional research is needed to determine whether these conclusions apply to other decision-support tools and larger networks.University of Delaware, Civil, Construction and Environmental EngineeringPh.D
Predictive habitat occupancy models for North American river otters along inland streams in New Jersey
No full textThis article was originally published in Wildlife Biology: A journal for wildlife science. The version of record is available at: https://doi.org/10.1002/wlb3.01367.
© 2025 The Author(s). Wildlife Biology published by John Wiley & Sons Ltd on behalf of Nordic Society Oikos.
This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/3.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.The North American river otter Lontra canadensis is a semi-aquatic furbearer species that historically ranged throughout North America. Starting in the mid-1800s and continuing through the early 1900s, the negative effects associated with anthropogenic disturbances (i.e. overharvest, development and ultimately habitat alternation) led to local extinctions. Researchers debate whether current land use patterns are affecting river otter occupancy. New Jersey is the most densely populated state in the United States, thus it provides a perfect study area to test potential anthropogenic effects on river otters. Using occupancy modeling to examine river otter habitat preferences, we measured presence/absence at 244 low order streams from January–April 2011–2012 along with 19 corresponding site/landscape covariates in both northern and southern New Jersey. In southern New Jersey, we detected otters at 83/141 sites (58.9%) with a detection probability of 97.7% across repeat visits and a predicted occupancy of 59.4 ± 0.04%. In northern New Jersey we detected otters at 31/103 sites (30.1%) with a detection probability of 44.5% across repeat visits and a predicted occupancy of 58.8 ± 0.04%. We determined the influence of habitat covariates on otter occupancy and found that water depth, water quality, stream width and mink presence were positively correlated with otter occupancy. The % commercial, industrial, transportation and recreational habitat, % low intensity development, bank slope, and distance to lake were negatively correlated with otter occupancy. Knowing the location of occupied stream and latrine sites will assist biologists in their efforts to monitor river otter populations and help estimate river otter density for harvest and conservation efforts.Research funding was provided in part by the Endowed Waterfowl and Upland Gamebird Center at the University of Delaware and by USDA Hatch (DEL00854)
Civil Disobedience in Democratic Education
No full textThis article was originally published in Integrative Psychological and Behavioral Science. The version of record is available at: https://doi.org/10.1007/s12124-024-09888-y.
© The Author(s) 2025.
Open Access This article is licensed under a Creative Commons Attribution 4.0 International License, which permits use, sharing, adaptation, distribution and reproduction in any medium or format, as long as you give appropriate credit to the original author(s) and the source, provide a link to the Creative Commons licence, and indicate if changes were made. The images or other third party material in this article are included in the article's Creative Commons licence, unless indicated otherwise in a credit line to the material. If material is not included in the article's Creative Commons licence and your intended use is not permitted by statutory regulation or exceeds the permitted use, you will need to obtain permission directly from the copyright holder. To view a copy of this licence, visit http://creativecommons.org/licenses/by/4.0/.The study’s goal was to examine the tension between democratic school governance, requiring its participants to obey school rules, even though they might disagree with those rules, and personal responsibility, requiring the participants to act morally, in accordance with their conscience and their sense of what is right and makes sense for them, regardless of the democratic nature of the imposed school rules. This examination was based on three sources: 1) three Open Symposia with American and Russian democratic educationalists, 2) my review of the existing literature on civil disobedience and democratic education, and 3) my empirical study based on the interviews of participants of an American private democratic school, known as The Circle School, regarding their instances of civil disobedience. The three Open Symposia allowed me to develop a working definition of civil disobedience as a particular principled disobedience. One important finding arising from these Open Symposia was that neither democratic educator could come up with an example of civil disobedience in democratic schools. My literature analysis revealed four types of civil disobedience: instrumental, existential, safeguarding, and expedient. The participants of my interviews in a democratic school – current teenage students, staff, and alumni – reported many instances of diverse types of civil disobedience, but primarily existential. Despite a lack of discussions of civil disobedience in the school, I discovered that the democratic school apparently promotes civil disobedience as its unintended curriculum by promoting and supporting students’ authorial agency, aiming at the students deciding what is good for them, and opposing educational paternalism
Staging an Experience of Cultural Heritage Preservation: Consumers' Willingness to Pay for Heirloom Rice in the Philippines
No full textThis article was originally published in Agribusiness. The version of record is available at: https://doi.org/10.1002/agr.22019.
Agribusiness© 2025 The Author(s). Agribusiness published by Wiley Periodicals LLC.
This is an open access article under the terms of the Creative Commons Attribution-NonCommercial-NoDerivs License (http://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.The Cordillera Administrative Region in the Philippines is home to terraced rice embedded in centuries of cultural heritage. However, weak market incentives threaten sustained production, jeopardizing indigenous communities' cultural heritage and the in situ biodiversity of rice genetic resources. Demand-side policy interventions have been proposed to address these challenges. Drawing on the experience economy, we staged an experience with urban consumers, offering them the opportunity to participate in cultural heritage preservation through purchasing heirloom rice. Participants first self-selected into white or brown rice market segments as a benchmark. Subsequently, each market segment was invited to (i) identify their preference between their benchmark and heirloom rice, and (ii) bid to upgrade their non-preferred to their preferred rice through a Becker-DeGroot-Marschak (BDM) mechanism. The sample was randomly split between a control group and two “experience treatment” groups exposed to gain- or loss-framed narratives about rice terrace preservation. Results reveal that a subset of consumers in each market segment switched to heirloom rice. White rice consumers were more reluctant to transition to heirloom rice, although they responded positively to the gain-framed narrative, paying the highest price premiums for heirloom rice (PhP 92.55 or US $2.03 per kilogram). Brown rice consumers were more willing to switch but willing to pay lower premiums for heirloom rice, altogether suggesting the need for a segmented marketing strategy. Highlighting nutritional benefits and quality is crucial, but positioning heirloom rice within a gastronomic system that showcases its use in specific dishes and occasions is equally important for enhancing consumer appeal.We would like to thank all funders who supported this research through their contributions to the CGIAR Trust Fund: http://www.cgiar.org/funders/. Financing from the Philippines Department of Agriculture through the Heirloom Rice Project (Raising Productivity and Enriching the Legacy of Heirloom/Traditional Rice through Empowering Communities in Unfavorable Rice-Based Ecosystem), the CGIAR Research Program on Rice, the CGIAR Initiative on Market Intelligence, and the CGIAR Science Program on Better Diets and Nutrition are gratefully acknowledged