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Development of a Water Temperature Modeling Platform to Support Short- and Long-Term Water Temperature Management in Reservoir-River Systems
No full textThe U.S. Department of the Interior, Bureau of Reclamation (Reclamation) supports water temperature management for fishery species protection in downstream river reaches below Central Valley Project (CVP) reservoirs in the Sacramento, American, and Stanislaus River systems. The Water Temperature Modeling Platform (WTMP) Project was initiated to modernize and enhance modeling capabilities to predict summer–fall water temperature through reservoir cold water pool management using temperature control facilities designed for temperature management. The WTMP supports forecasts, historical analyses, and long-term planning efforts and advances previous modeling approaches by using an integrated modeling platform. This platform includes a data management system that acquires real-time data, provides quality assurance methods, and yields model-ready data for simulations; a modeling framework that manages model input file construction for multiple models, controls selected model simulation for reservoir and/or river reaches, and manages model output; and an automated reporting feature providing efficient and comprehensive reporting of tabular and graphical output for assessment and analysis by technical teams and decision-makers. The WTMP takes advantage of technological advancements in simulation models, available software, and databases to support Reclamation’s short- and long-term water temperature management needs. The platform is also adaptive for future integration with new or improved models and tools
Honoring Childhood Agency in Developmental Research: Best Practices, Applications, and Insights
No full textPediatric research requires caregivers to provide informed consent on behalf of their children. While not a formal requirement for children under the age of seven, it is important to involve child participants in the assent and decision-making processes in developmentally appropriate ways. This is especially important in longitudinal research, where the extent to which a developing child understands study tasks evolves over time. Although there is consensus that assent procedures are important and necessary, limited resources synthesizing strategies for pediatric researchers to encourage positive and respectful research experiences for young children exist. We describe methods used in an ongoing longitudinal study following caregiver-infant dyads from gestation through five years of child age. Study visits include repeated assessment of children’s behavioral, cognitive, and physical development. Additionally, we describe observations from a study that used art-based approaches to enhance agency during study visits with five-to ten-year-olds. We describe methods for promoting agency in research contexts including potential modifications based on developmental milestone achievement. We detail strategies for assessing and responding to child behaviors that may indicate dissent. By synthesizing this information, we provide a comprehensive resource that may be used to encourage positive and respectful research experiences for children. Such experiences are likely to improve data quality and retention and uphold developmental research ethics. Further, this work contributes to a larger conversation about child agency, which has been occurring for decades across academic disciplines. Promoting children’s agency in research also has potential to promote healthy long-term outcomes for developing childre
2025 Commencement College of Education Ceremony Video
No full textVideo presentation of the PSU College of Education Commencement ceremony, held June 14, 2025, at the Viking Pavilion at Portland State University.https://pdxscholar.library.pdx.edu/commencement_2020s/1017/thumbnail.jp
Systematics and Phylogeography of \u3ci\u3eMundochthonius\u3c/i\u3e Chamberlin, 1929, in the Pacific Northwest (Chelicerata, Pseudoscorpiones)
No full textUnderstanding the processes that drive genetic divergence and species formation is central to evolutionary biology. Invertebrates with low dispersal ability, such as pseudoscorpions, are especially prone to cryptic diversification due to their occupancy of niche microhabitats and sensitivity to landscape barriers. Despite their ecological roles as predators and bioindicators, pseudoscorpions remain one of the least studied arachnid groups, with limited taxonomic resolution and few integrative studies. This research focuses on the genus Mundochthonius in the Pacific Northwest, particularly M. pacificus, a morphologically conserved species whose true diversity and distribution remain poorly understood.
Field surveys guided by a GIS-based habitat suitability model were conducted across Oregon, Washington, Idaho, and Montana. A total of 56 individuals were sequenced for mitochondrial COI and 25 for nuclear 28S, revealing eight geographically structured COI clades and an east–west split across the Cascade Range. Inland populations formed a distinct eastern clade (M. sp.), genetically divergent from M. pacificus and likely representing an undescribed species. The range of M. pacificus found in this study was limited to the west side of the Cascade Range, extending from King County, Washington, to Humboldt County, California.
To assess whether these genetic lineages corresponded with morphological differentiation, morphometric analyses were conducted on 103 specimens using light microscopy and scanning electron microscopy (SEM). The most consistent morphological differences were found in coxal spine structure and multivariate comparisons of body proportions, with M. sp. distinguishable from M. pacificus and M. magnus. Although some overlap in morphometric traits was observed, particularly within M. pacificus, these data supported species-level divergence.
This study presents the first phylogeographic and integrative taxonomic analysis of Mundochthonius in North America. Results highlight cryptic diversity within the genus and identify the Cascade Range as a primary biogeographic barrier. These findings underscore the value of combining genetic, morphological, and geographic data to resolve species boundaries in poorly studied arthropod groups
Emergence of Norms in the Presence of Social Network Structure in a Stochastic Evolutionary Game Theory Model
No full textIn their 2000 paper, The Emergence of Classes in a Multi-Agent Bargaining Model, Axtell, Epstein, and Young introduced an agent-based bargaining model to study how social norms can emerge and persist from the decentralized, asynchronous interactions of individual agents in the presence of noise, even when these agents have no predefined preferences or advantages. This thesis extends their model by incorporating structured interaction networks, allowing us to investigate how the topology of agent interactions influences long-run dynamics and norm formation. Using a custom simulation package built in the Julia programming language, we replicate the original results under a complete interaction graph and then conduct a comparative analysis using four random graph models: Erdős-Rényi, Small-World, Scale-Free, and Stochastic Block Models. We analyze noise-induced transitions from the metastable, discriminatory fractious state to the stochastically stable equity norm, highlighting how structural features such as degree heterogeneity, clustering, and community structure shape both the inertia, i.e., waiting time until transition, and the dynamical path of normative convergence. Our findings emphasize that differences in network topology affect the speed, variability, and trajectory of population-level transitions. To ensure meaningful comparison across models, we use a systematic approach to parameterization and introduce a revised stopping condition, the partially-reinforced equity condition, which more accurately captures system inertia and enables simulations at larger population scales. This thesis contributes both methodological tools and theoretical insights to the study of evolutionary game theory, social learning, and complex adaptive systems
Polynomial-Time Constant-Approximation for Fair Sum-Of-Radii Clustering
No full textIn a seminal work, Chierichetti et al. [20] introduced the (t,k)-fair clustering problem: Given a set of red points and a set of blue points in a metric space, a clustering is called fair if the number of red points in each cluster is at most t times and at least 1/t times the number of blue points in that cluster. The goal is to compute a fair clustering with at most k clusters that optimizes certain objective function. Considering this problem, they designed a polynomial-time O(1)- and O(t)-approximation for the k-center and the k-median objective, respectively. Recently, Carta et al. [15] studied this problem with the sum-of-radii objective and obtained a (6 + ϵ)-approximation with running time O((klog1+ϵ(k/ϵ))knO(1)), i.e., fixed-parameter tractable in k. Here n is the input size. In this work, we design the first polynomial-time O(1)-approximation for (t,k)-fair clustering with the sum-of-radii objective, improving the result of Carta et al. Our result places sum-of-radii in the same group of objectives as k-center, that admit polynomial-time O(1)-approximations. This result also implies a polynomial-time O(1)-approximation for the Euclidean version of the problem, for which an f(k) · nO(1)-time (1 + ϵ)-approximation was known due to Drexler et al. [24]. Here f is an exponential function of k. We are also able to extend our result to any arbitrary ℓ ≥ 2 number of colors when t = 1. This matches known results for the k-center and k-median objectives in this case. The significant disparity of sum-of-radii compared to k-center and k-median presents several complex challenges, all of which we successfully overcome in our work. Our main contribution is a novel cluster-merging-based analysis technique for sum-of-radii that helps us achieve the constant-approximation bounds
Unshrouding Narratives, Beliefs, and Practices Related to the Aye-Aye (daubentonia Madagascariensis) in Eastern Madagascar
No full textEthnoprimatology emphasizes the complex sociocultural dimensions of human-alloprimate interactions, often overlooked in conservation practices and narratives shaped by ecological perspectives alone. In Madagascar, lemurs are deeply embedded in local traditions structured around taboos, legends, and kinship beliefs. Among them, the aye-aye ( Daubentonia madagascariensis ) is frequently subject to a narrative portraying it as an evil animal, an omen, or a harbinger of misfortune. Yet, cultural representations of the aye-aye across Madagascar are far more diverse. While some reports describe ritual killings, others recount respectful mortuary practices bestowed upon these primates. We explored the beliefs, narratives, and practices associated with the aye-aye in three regions of eastern Madagascar. Drawing on a mixed-methods approach, we combined quantitative and qualitative data from 219 semistructured interviews with grounded theory methodology and developed an interpretive framework for understanding the species’ cultural representations. Our results revealed a wide variety of traditions, including magical and therapeutic uses of aye-aye body parts and three legends underpinning these belief systems. We propose that these traditions stem from the belief that the aye-aye is inhabited by a spirit, whether evil or ancestral. Responses to its perceived nefarious powers vary from ritual display of the killed animal to mortuary practices comparable to human funerals. These findings urge a shift away from reductive narratives long popularized in recent decades, recognizing complexity and site-specificity. Similar to other contemporary ethnoprimatologists, we advocate for a cautious, context-sensitive approach to both reporting lemur-related traditions and designing conservation programs, emphasizing the need for carefully considering the religious systems that underlie practices involving threatened species
The Web of TPD Reform: a Reflective Tool for Analyzing and Improving Teaching Professional Development Programs for Teaching Assistants
No full textTeaching assistants (TAs) play a pivotal role in the teaching mission of higher education, but too often they are asked to do this important job without adequate teaching professional development (TPD). By receiving training in inclusive and evidence-based teaching practices, TAs can in turn help disseminate effective teaching methods for the benefit of students throughout the nation; as future faculty, TPD also better prepares TAs for their careers, helps solve longstanding problems of inclusion and retention in STEM, and reforms disciplinary educational norms through cultural evolution. Thanks to prior research and advocacy efforts, there is a growing awareness that STEM education needs to do more to help support these instructional allies in the present and to prepare them to do a more effective job teaching the next generation of scientists and citizens. To aid in this disciplinary transformation, we introduce the Web of TPD Reform, an evidence-based reflective tool for creating, improving, and studying TA-TPD. Expanding on the work of the Building a Better Future STEM Faculty report, we define 16 features of TA-TPD programs, each of which can be categorized or evaluated on a five-point scale. The web is useful for institutions when envisioning new TA-TPD, as well as for reflecting on and reforming existing TPD programming; it may also serve as a research tool for tracking key metrics of TPD. Here, we describe our rationale, present the TPD Web, walk readers through its use, and discuss example applications
Practice Research Collaboratives: Promising Communities of Research?
No full textPurpose: This article reflects an analysis of the establishment and development of the Practice Research Collaborative on Organizational Supports (PRC-OS) within the International Community of Practice Research. The basic thesis concerns the importance of building intersecting special interest groups to form communities of research practice.
Methods: The study is a qualitative case study, consisting of diverse data as written documents, field notes, and participative observation. A thematic and abductive analysis was conducted.
Results: Sharing of practices and knowledge, values and ethos are important factors to develop the PRC-OS, as is also negotiations on participation and organization. These themes are intertwined and must be considered important factors that need continuous attention and negotiation in order for the collaborative to sustain and thrive. Discussion: Contextualized within theories on communities of practice, the PRC-OS facilitates for a trialogical learning process and it develops in cyclical phases of commitment, start-up, and operating
Aquatic Invasive Species Survey and Treatment on Lake Umatilla and Lake Celilo 2023-2024 Report
No full textFlowering Rush (Butomus umbellatus) is an invasive aquatic plant in the Pacific Northwest that threatens salmon habitat. The Center for Lakes and Reservoirs staff surveyed for this and other aquatic species from 2023 and 2024 in the Columbia River in Lake Umatilla and Lake Celilo. This document summarizes their survey efforts including their protocols, data, and small-scale removal efforts