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Quasi-Static Electro-Mechanical Response of Circular Dielectric Elastomer Membranes Under DC Voltages
No full textDielectric elastomers have attracted significant attention because of their large voltage-induced mechanical strains, fast response times, high specific elastic energy (3.4 J/g), and strong electro-mechanical conversion efficiency. Circular dielectric elastomer membrane actuators (DEAs) have proven valuable for evaluating new elastomers, electrodes and their combinations; eliciting interesting vibratory and dynamic response; and validating new electro-mechanical constitutive models and membrane mechanics models. Despite their practical importance, experimental data quantifying the quasi-static voltage-stretch response of circular DEAs under the action of DC voltages is limited. To address this, we perform an experimental program designed to interrogate the impact of electrode diameter and membrane pre-stretch on the quasi-static electro-mechanical response (e.g., voltage vs. stretch, electrical breakdown, and eccentricity of the active area) of circular DEAs. When the electrode diameter is held constant and the pre-stretch is varied, membranes with larger pre-stretches exhibit greater voltage-induced deformations and transition into a more compliant electro-mechanical regime at lower voltages. When the pre-stretch is fixed and the electrode diameter is varied, the tests revealed that smaller electrodes produced larger stretch magnitudes and more compliant behavior, while larger electrodes resulted in stiffer responses. The findings from this study provide meaningful insight into the electro-mechanical coupling mechanisms that govern soft dielectric actuators. In particular, the results reinforce the critical role of pre-stretch in stabilizing membrane actuation and mitigating electro-mechanical instability
Father James L. Heft Lecture on St. John Henry Newman, Doctor of the Church
No full textIn this recorded lecture, Father James L. Heft, S.M., provides history, commentary, and reflection about St. John Henry Newman, who became a Doctor of the Catholic Church on Nov. 1, 2025.
The recording is a collaboration of the Institute for Pastoral Initiatives (IPI), the Learning Teaching Center (LTC), and the Department of Religious Studies at the University of Dayton.
Sources to which Father Heft refers in the lecture: Newman 101 by Roderick Strange John Henry Newman: A Biography by Ian Ker The Parting of Friends by St. John Henry Newman An Essay on the Development of the Christian Doctrine by St. John Henry Newman On Consulting the Faithful in Matters of Doctrine by St. John Henry Newman Grammar of Assent by St. John Henry Newman Lectures on the Prophetical Office of the Church by St. John Henry Newma
Partition, Passport and the Documentary Life of Belonging
No full textAs India and Pakistan emerged as two new nation-states after 1947, questions around nationality and citizenship animated official and public discourses. While there were constitutional and legal pronouncements to clarify these matters, this article suggests that particular documents governing mobility became central to how such issues were framed and understood. In particular, this article focuses on the Indian passport and similar documents of mobility control, such as the domicile certificate, permits, and so on, to examine how they worked singly and in conjunction to frame the documentary life of belonging. The article also focuses on particular mobile groups, Muslim minorities and women married to non-Indians, to understand how these documents became central to their claims of citizenship and belonging
The Effect of Explicit Writing Instruction on Students’ Writing Ability and Content Knowledge Comprehension in a Middle School Social Studies Classroom
No full textImplementation of writing in the content areas has been encouraged since the 1960s and 1970s. Yet, there is minimal research on how to effectively deliver this instruction in the classroom (Galbraith & Baaijen 2018). Teachers utilize activities such as free writing, journaling, and argumentative writing to promote learning, but there is little evidence that teachers of different content areas provide the explicit writing instruction students need to successfully write in the specific content area (Graham, Kiuhara & MacKay, 2020). The main question explored in this study is, “Does explicit writing instruction in the content area of social studies in a middle school classroom influence students\u27 writing ability and content knowledge retention?” The hypothesis is that while most students will make some progress in understanding the content materials, students who receive the intervention will make greater progress in developing content knowledge through writing with instruction. There were two main objectives while conducting this research: 1) Explore how explicit writing interventions in a social studies classroom at the middle school level impacts student understanding in the classroom, 2) Develop a deeper understanding of how different instruction that teachers provide in social studies impacts students\u27 writing abilities. To determine the effect of explicit writing instruction in a different content area on students’ writing abilities and content 3 knowledge in middle school classrooms, the intervention of a single paragraph outlining template was implemented in the content area classroom of social studies. A triangulation of data was implemented throughout this research. Interviews were conducted with the teachers for both pre-intervention implementation and post-intervention implementation. Documents of students\u27 work samples were collected and analyzed. Finally, observations of the writing instruction in each classroom were conducted
Assessing Groundwater Recharge Dynamics: A Comparative Study of Stable Isotope and Hydrological Modeling Approaches in the Omo Gibe River Basin, Ethiopia
No full textThis study assesses groundwater recharge dynamics in the Gilgel Gibe, Gombora, and Neri watersheds of the Omo Gibe River Basin (OGRB), Ethiopia, using a comparative approach that integrates stable isotope mass balance and the WetSpass-M hydrological models. The research aims to analyze isotopic compositions of precipitation and groundwater, estimate seasonal and spatial groundwater recharge rates, and evaluate the performance of both models across diverse hydro-climatic zones. The stable isotope approach involved analyzing δ18O and δ2H compositions to establish Local Meteoric Water Lines (LMWLs), seasonal distribution of isotopes, and quantifying seasonal recharge contributions using the oxygen-18 mass balance method. Concurrently, using meteorological and physical data, the WetSpass-M model simulated monthly water balance components, including recharge, surface runoff, and evapotranspiration. Model calibration, validation, and sensitivity analysis were performed using observed streamflow data. Key findings indicate that groundwater recharge is primarily driven by wet-season precipitation, with minimal contributions from the dry season. An isotope analysis revealed that 88.1% and 83.7% of recharge in the Gilgel Gibe and Gombora watersheds, respectively, occur during the wet season. In contrast, the Neri watershed exhibits a more balanced distribution due to its bimodal rainfall pattern. The WetSpass-M model confirmed these results, showing peak recharge during the wettest months and emphasizing the influence of land cover, soil properties, and precipitation. Both methods agreed strongly on seasonal recharge patterns, with isotopes providing direct field-based estimates and WetSpass-M offering high-resolution spatial insights. The study concludes that combining stable isotope techniques with hydrological modeling improves the accuracy and reliability of recharge assessments. It highlights the critical role of wet-season precipitation in sustaining groundwater and underscores the need for tailored water resource management strategies, including land-use planning and climate adaptation measures. This research provides a methodological framework for sustainable groundwater management in the OGRB and similar regions, offering valuable insights for future hydrological studies
Design and Fabrication of Tunable Photonic Devices Using Phase-Change Materials
No full textThe advancement of photonic and semiconductor technologies increasingly depends on materials and fabrication methods that enable dynamic, high-resolution, and scalable architectures. Phase change materials (PCMs), such as vanadium dioxide (VO2) and germanium antimony telluride (GST), offer reversible phase transitions with significant optical and electrical modulation. This dissertation presents three projects that integrate PCMs into reconfigurable optical components and lithographic processes, leveraging their unique switching behavior. The first project demonstrates a thermally tunable VO2 wire-grid polarizer operating in the mid-wave infrared (MWIR), with a 6 dB extinction ratio. A scalable fabrication workflow is presented to streamline the photolithographic patterning of vanadium. The second project introduces a low-cost photothermal lithography method using PCM thin films, enabling sub-diffraction patterning down to 300 nm with \u3c10 nm sidewall roughness and near-100% yield under relaxed conditions. The final project presents an electrically biased GST-based tunable mid-IR filter. Electric switching enables index tuning, while maintaining angular-independent resonance up to 60°. These works underscore the potential of PCMs in dynamic photonic systems and scalable nanomanufacturing
Intersectional Study of the Impact of Principal Leadership on Black Girls in Special Education
No full textThe purpose of this participatory action research study is to amplify the treatment of Black girls, as students with disabilities, around disproportionality, access to the general education curriculum and environment, and adultification stereotypes. The study, using a qualitative methodology and phenomenological lens, illuminates the leadership needs of principals around special education processes to better serve Black girls with disabilities. The findings underscore how Black principals see Black girls with disabilities differently than their teachers, teachers misinterpreting Black girls\u27 traumas, racialized approaches to identifying minority students with disabilities through the RtI process, and the caring and uncaring of Black girls\u27 learning capacities. The implications of this study pose a threat to special education practices, processes, and policies that loosely promote fair treatment of minority students
One Last Stop
No full textOne Last Stop, by Casey McQuiston, is a heartfelt queer rom-com that blends romance, mystery, and a touch of magical realism as it follows August, a guarded newcomer to New York City, whose life is transformed when she meets Jane, an effortlessly cool lesbian who also happens to be displaced in time. Through found family, late night diners, and the electric city, McQuiston crafted a story about love that defines logic and the courage it takes to open your heart. As August works to uncover Jane’s past and bring her home, she discovers her own place in the world. This novel is a joyful read that discovers the connection and magic between the two characters.https://ecommons.udayton.edu/ul_popularromance/1108/thumbnail.jp
Conceptual Diagrams Help Dietetic Students to Understand and Apply the Nutrition Care Process
Get PDFAim: To evaluate the impact of a conceptual diagram assessment task on dietetic student knowledge of and confidence applying the Nutrition Care Process. Methods: Situated within a pragmatic research paradigm, this mixed methods study applied a survey administered before and after a conceptual diagram assessment task using the Nutrition Care Process to explore changes in student knowledge, self-reported confidence, perceptions towards the Nutrition Care Process, and student experience. Nineteen students enrolled in a first-semester unit within a Master level dietetic course completed the assessment task, which visually presented a client case sourced from the student-run clinic within the Nutrition Care Process framework, as an adjunct to traditional teaching. Wilcoxon Signed-Rank test determined changes in knowledge and the McNemar test determined changes in self-reported confidence and perspective. Open-ended responses were thematically analyzed. Results:Knowledge scores (maximum of 10) significantly increased following participation in the assessment task (before 5.63 ± 1.67, after 8.36 ± 1.16, P Conclusions: Using conceptual diagrams alongside client cases is a novel and effective education tool to help dietetic students understand and apply the Nutrition Care Process as part of a system of assessment