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Beaver Versus Human: The Big Differences in Small Dams
No full textThis article was originally published in WIREs: Water. The version of record is available at: https://doi.org/10.1002/wat2.70019.
© 2025 The Author(s). WIREs Water published by Wiley Periodicals LLC.
This is an open access article under the terms of the Creative Commons Attribution License (http://creativecommons.org/licenses/by/4.0/), which permits use, distribution and reproduction in any medium, provided the original work is properly cited.As beavers (Castor spp.) are reintroduced to streams in the northern hemisphere and nature-based and process-based river restoration emphasizes human-built analogues for beaver dams, it is reasonable to ask how beaver dams and ponds compare to different types of small dams constructed by humans for diverse purposes. We use published research as a basis for comparing the effects of beaver dams and four types of human dams—beaver dam analogues, earthen embankments perpendicular to flow that are used to create stock ponds, check dams, and mill dams. We compare these dams with respect to water balance and three-dimensional hydrologic connectivity, sediment, particulate organic matter and carbon, nutrients, habitat, and biota. These assessments inform us in ranking small dams from generally most beneficial with respect to providing ecosystem services (beaver meadows with multiple dams) to least beneficial (mill dams), recognizing that beaver meadows may not be beneficial at some sites for infrastructure and human property within the river corridor, and mill dams may be beneficial at some sites where they impede upstream migration by invasive species or provide lentic habitat in the river corridor. This comparison among dam types highlights the need for research on the cumulative effects of multiple small dams along a river corridor and across a river catchment, as well as identifying gaps in our understanding of the effects of specific types of dams, including the effects of stock ponds and check dams on carbon and nutrient dynamics.
Graphical Abstract available at: https://doi.org/10.1002/wat2.70019
Illustration of the net benefits and costs of different types of dams considered in this paper. The types of dams are ordered by relative benefit from left to right, with the most beneficial on the left. The number of + symbols under benefits and − symbols under costs indicate the likely magnitude of the effect, from + for small effect to +++ for substantial effect. The inset photo for the earthen embankment is a Google Earth view (with scale bar) for a stock pond in Wyoming
Regional Differences in U.S. Consumer Preferencesfor Native Woody Shrubs With Varying AestheticCharacteristics
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). Agribusiness published by Wiley Periodicals LLC
This article was originally published in Agribusiness. The version of record is available at: https://doi.org/10.1002/agr.70030Native plants offer a variety of aesthetic (e.g., fall colour, fruit, flowers) and functional benefits (e.g., pollinator friendly, wildlife friendly, water management). How these benefits influence consumer choice and perceived value of native versus introduced plants is not well understood. Additionally, the geographic location of the consumer may influence his/her preferences for native species. The present study used an online survey with a discrete choice experiment to elicit regional differences in 2011U.S. consumers’ preferences for native and introduced woody ornamental plant species with fall colour, fruit, and flower characteristics. Results suggest preferences for native plants versus introduced plants rely heavily on the specific type of plant presented, likely due to differences in aesthetics and preferences. Generally, participants had stronger preferences for native plants than introduced species. However, some differences arose. In the fruit and flower aesthetic benefits, one of the native species was valued more than the introduced species, while in the fall colour aesthetic one of the native species was valued less than the introduced species. Regional differences were noted. Industry implications include clearly articulating when a native plant is presented in the retail centre to allow customers to make informed decisions based on their own values and to highlight plant benefits that align with regional needs.Funding for the project was provided by the Horticulture Research Institute (HRI). Its contents are solely the responsibility of the authors and do not necessarily represent the views of HRI
Biases in Perceiving Positive Versus Negative Emotions: The Influence of Social Anxiety and State Affect
No full textThis article was originally published in [Journal Name]. The version of record is available at: https://doi.org/10.3390/vision9040092
© 2025 by the authors. Licensee MDPI, Basel, Switzerland. This article is an open access article distributed under the terms and conditions of the Creative Commons Attribution (CC BY) license (https://creativecommons.org/licenses/by/4.0/).Models suggest social anxiety is characterized by negative processing biases. Negative biases also arise from negative mood, i.e., state affect. We examined how social anxiety influences emotional processing and whether state affect, or mood, modified the relationship between social anxiety and perceptual bias. We quantified bias by determining the point of subjective equality, PSE, the face judged equally often as happy and as angry. We found perceptual bias depended on social anxiety and state affect. PSE was greater in individuals high (mean PSE: 8.69) versus low (mean PSE: 3.04) in social anxiety. The higher PSE indicated a stronger negative bias in high social anxiety. State affect modified this relationship, with high social anxiety associated with stronger negative biases, but only for individuals with greater negative affect. State affect and trait anxiety interacted such that social anxiety status alone was insufficient to fully characterize perceptual biases. This raises several issues such as the need to consider what constitutes an appropriate control group and the need to consider state affect in social anxiety. Importantly, our results suggest compensatory effects may counteract the influences of negative mood in individuals low in social anxiety.This research received internal funding from the University of Massachusetts Boston Office of the Dean (vmc, shs) and University of Massachusetts Boston undergraduate research funds (dah, em)
Effects of fibrillating PTFE on transfer, wear, and friction
No full textBurris, David L.Davis, ChelseaSolid lubricants are crucial in applications where conventional liquid lubricants fail due to extreme environmental conditions, such as high temperature, high pressure, or chemical exposure. Among these, polytetrafluoroethylene (PTFE) stands out for its exceptional low friction properties. However, its high wear rate poses a significant challenge, limiting its effectiveness and long-term reliability in demanding tribological applications. Traditional fillers and even nano fillers have successfully reduced wear by orders of magnitude through presumed mechanisms that include crack arresting, mechanical load support, and improved transfer film adhesion. There is emerging evidence, however, that the most successful of these promote PTFE fibrillation, a unique process where PTFE chains unfold and create an expanded network of fibrils and nodes under mechanical stress. Fibrillation is native to PTFE prior to melt processing but not after. The retention of fibrillation of PTFE due to the inclusion of nanofillers would be expected to enhance transfer film adhesion and stability, which in turn reduces friction and wear. To date, this potential wear reducing role of nanofillers has not been considered or studied. ☐ This research seeks to address this gap by isolating and studying the effects of fibrillation on PTFE tribological performance in the absence of fillers. My hypothesis is fibrillating PTFE can reduce wear and friction through enhancing nanoscopic fibrils anchoring to the countersurface under standard sliding conditions. The aim is to retain fibrillation within melt-processed PTFE parts and study its effects on PTFE transfer, wear, and friction. ☐ This work proposes and tests an entirely new parallel wear reduction mechanism of nanofillers in PTFE, isolates and assesses the effect of PTFE fibrillation on its tribology for the first time, and adds new insight into the nature of ultra-low wear and its practical limitations. ☐ Keywords: PTFE, Transfer film, Fibrillation, Wear, Friction, Nanofiller.University of Delaware, Department of Mechanical EngineeringM.S
Mathematical modeling of HOX gene regulation in colorectal cancer
No full textSchleiniger, Gilberto F.Boman, Bruce M.Human HOX genes are essential transcription factors that govern embryonic development and play critical roles in tumorigenesis. In colorectal cancer (CRC), their expression is tightly regulated by both the WNT and retinoic acid (RA) signaling pathways. While prior studies have explored these pathways individually, limited work has addressed their combined influence on CRC progression. This dissertation bridges that gap by introducing a novel mathematical model that captures the dynamic interactions among the HOX, WNT, and RA pathways. We develop a system of nonlinear ODEs to describe the reaction kinetics within a complex biochemical network involving these three pathways, which are fundamental to tissue homeostasis and cancer development. ☐
The model focuses on two key HOX genes, HOXA5 and HOXA13, which are differentially involved in CRC development and treatment response. By incorporating these genes within the RA and WNT regulatory networks, the model captures the antagonistic relationship between HOXA5 and WNT signaling, mediated in part through repression by the MYC:MIZ1 complex. This complex plays a crucial role in stemness regulation by inhibiting HOXA5 transcription. Simulation results support biological findings that highlight HOXA5 as a tumor suppressor and a potential biomarker in CRC, particularly through its inverse regulation of WNT activity. ☐ Moreover, the model integrates CYP26A1, an enzyme that metabolizes RA and mediates feedback between the WNT and RA pathways. This addition enables the simulation of all-trans retinoic acid (ATRA) treatment, revealing that CYP26A1 activity can counteract or override the therapeutic effects of ATRA. The findings suggest that under wild-type APC (wt-APC) conditions, simultaneous modulation of ATRA levels and CYP26A1 expression may enhance treatment efficacy, offering a new direction for targeted CRC therapy.University of Delaware, Department of Mathematical SciencesPh.D
The effects of process-oriented feedback and revisions on middle schools' fraction arithmetic performance
No full textBarbieri, Christina AreizagaFoundational fraction knowledge is critical for students’ long-term success in mathematics and in both STEM and non-STEM careers (Barbieri et al., 2019; Handel, 2016). The middle school years represent a key developmental stage when math becomes more challenging and achievement often begins to decline (Cleary & Chen, 2009; Wang & Pomerantz, 2009). Prior research suggests that two strategies, process-oriented feedback and opportunities to revise, can improve student learning, but few studies have examined their combined effects in middle school mathematics classrooms. This study extends existing research by experimentally testing the effects of varying feedback types and revision opportunities on students’ fraction arithmetic performance. ☐ Using an experimental design, 103 sixth- to eighth-grade students from two schools in the Northeastern U.S. were randomly assigned to one of three conditions: (1) process-oriented feedback with revision (POF+OTR), (2) answer feedback with revision (AF+OTR), or (3) process-oriented feedback without revision (POF). Students completed a pretest, participated in a one-on-one audio-recorded training session where they reviewed their pretest responses, and then completed a posttest. I analyzed the main effects of conditions on posttest scores using multiple linear regression, controlling for pretest performance and class-level fixed effects. I also explored aptitude-by-treatment interactions to assess whether prior knowledge moderated the effects of the conditions. To complement the quantitative analysis, I conducted an inductive thematic analysis of think-aloud transcripts and written responses from 25 students, identifying four key themes: feedback engagement, feedback interpretation, strategies for correction, and emotional/metacognitive responses. Additionally, I conducted an error analysis to track the persistence or change in error types (e.g., strategy and execution errors) from pretest to revised pretest and posttest. ☐ Results revealed no statistically significant differences in posttest performance between the three conditions. Additionally, students’ prior knowledge did not significantly moderate the effects of the three conditions. The qualitative analyses revealed that students who engaged more deeply with feedback tended to revise more effectively. These qualitative findings suggest that combining process-oriented feedback with revision may be more effective for addressing execution errors or procedural misunderstandings, while errors based on students' strategy use may require more intensive or sustained support. Notably, strategy errors remained more resistant to change across conditions.University of Delaware, School of EducationPh.D
TRANSCONTINENTAL CONFUSION: UNVEILING THE IDENTITY OF CIXIUS FRANCISCANUS STÅL (HEMIPTERA: FULGOROMORPHA: CIXIIDAE)
No full textenterThe cixiid planthopper Cixius franciscanus Stål, 1859 was described from
specimens asserted to be from San Francisco, California. Subsequent authorities have
interpreted the species in varied ways, culminating in the assertion that the species is
actually South American in origin. Here the species is redescribed and placed in a new
genus, Alviarus n. gen. as Alviarus franciscanus n. comb. based on available
specimens and the unpublished notes of the late Dr. Frank Mead. Further notes on the
American Pentastirini and the significance of preserving the illustrations and notes of
entomologists are discussed.ente
Comparison in overnight of speech consolidation between individuals with and without a diagnosis of dyslexia
No full textEarle, Frances SayakoThis research study investigated whether adults with dyslexia experience difficulties with overnight memory consolidation across different types of learning. Participants with and without a diagnosis of dyslexia completed three tasks designed to assess declarative memory (object recognition), procedural memory (serial reaction time), and speech-sound learning (discrimination and identification). Each task was administered in the evening and again the next morning to evaluate changes over a 12-hour period. Results demonstrated that declarative memory improved similarly across groups, supporting claims that this memory system remains intact in dyslexia. In contrast, individuals with dyslexia demonstrated weaker overnight retention on the procedural task, suggesting possible consolidation deficits. For speech-sound learning, the dyslexia group displayed greater gains overnight in identification, indicating potential differences in how sleep supports auditory memory. These findings suggest that memory consolidation in dyslexia may be domain-specific and influenced by task type, offering new insight into how sleep-related processes affect learning in this population.University of Delaware, Department of Psychological and Brain SciencesM.S
Grading and Ungrading in Democratic Dialogic Classes Situated in a Conventional Higher Education Institution
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/s12124-025-09903-w.
© 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/.This article explores the contentious role of grading and ungrading in democratic dialogic education within conventional higher education. It critiques summative assessment for undermining genuine education by prioritizing compliance over inquiry, fostering distrust, and penalizing mistakes vital for educational growth. While institutionally mandated grading persists, the author introduces flexible pedagogical regimes accommodating diverse learner needs, including options for ungrading. These approaches prioritize student autonomy, emphasizing self-education rather than educational paternalism and credentialism. Challenges include cultural resistance, institutional constraints, and "school toxification." Despite obstacles, the author advocates for transformative practices that honor students' rights to self-education and preserve the integrity of democratic pedagogy.No funding