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Objective: The present study aimed to better understand key conceptualizations and operationalizations of intraindividual variability (IIV). We expected that differing types and metrics of IIV would relate to one another and predict outcomes (academic achievement) similarly. Method: The sample comprised 238 young adults. IIV was computed within and across six measures – three related to math and three more generally cognitive; in each case, score was separated from response time. We computed three types of IIV (inconsistency, dispersion, and dispersion of inconsistency), across several metrics (standard deviation, coefficient of variability, residualized standard deviation), and assessed their interrelations, and their prediction of academic achievement. Results: Differing metrics of variability were related to one another, but variably so. For prediction, whether or not inconsistency IIV metrics were significant was highly dependent on the measure they were derived from, with or without the primary score for a given measure also included. For dispersion of inconsistency and dispersion, variability metrics were often significant, though this was eliminated in most cases when score was also included in models. Conclusions: By concurrently examining multiple metrics and types of IIV within the same set of measures, this study highlights the need to (a) clarify the type of IIV utilized and why; (b) clarify the rationale for the kinds of measures used to compute IIV, particularly dispersion; and (c) include score alongside timing. Doing so will likely improve the generalizability of IIV findings, and prompt future research avenues, both psychometric- (e.g., simulations) and clinical-related (e.g., across ages and populations). 

Collaborative infrastructure systems are vital for managing scarce resources, particularly where user behaviors influence system sustainability. This study examines the relationship between design of constructed water infrastructure and strategic behaviors, focusing on flood irrigation systems as an example of collaborative infrastructure. The objectives are to investigate 1) whether shared water infrastructure can be effectively modeled using the stag hunt game framework and 2) how network topology impacts the strategic stability of user cooperation. Flood irrigation relies on collective action, where users balance risks of collaboration failure against benefits of successful cooperation. This situation closely aligns with stag hunt dynamics, in which users choose between a higher-value but riskier collaborative strategy or a lower-value, safer independent option. A key challenge arises when users opt out, increasing the burden on remaining collaborators. We apply a game-theoretic model using risk dominance criteria to analyze stability across four distinct infrastructure topologies: linear, tree, bus, and star. Results identify star and bus topologies as Pareto efficient, where a bus topology offers greater economic efficiency through reduced infrastructure costs and a star topology enhances stability due to equitable distribution of influence and reduced dependencies. An agent-based simulation validates analytical findings by dynamically captures user interactions under uncertainty and showing a strong correlation with game-theoretic results. Consequently, this study confirms the applicability of stag hunt frameworks for analyzing collaborative water infrastructure and provides practical insights into how topology design can influence cooperative resilience. These findings enhance knowledge for sustainable improvement of collaborative infrastructure. 

With a diverse sample of community college (CC) students (n = 94), we investigated how the working memory (WM)-math relation may be moderated by aspects of acculturation, including cultural adoption and cultural maintenance. We predicted that higher levels of each of the above acculturation factors would improve math performance by way of reducing WM load (via cognitive load). Conversely, we expected a weaker WM-math correlation at lower levels of acculturation due to the increased variability in cultural factors and the adverse effect of lower acculturation on WM through heightened cognitive load. In this cohort, WM correlated with math performance, but acculturation did not significantly influence this relationship. Neither cultural adoption nor cultural maintenance moderated the WM-math association. Results suggest that individualized educational interventions based on acculturation status alone may not be an effective strategy. Instead, institutions such as schools and governmental agencies may focus on providing a better foundation for educational success by enhancing academic and non-academic support systems to promote equitable educational opportunities for all students. Further research should explore additional individual and/or demographic factors (e.g. socioeconomic status, experiences of discrimination, cultural background) to better understand these complex relations. 

Abstract The plants of the circumpolar Arctic occupy a dynamic system that has been shaped by glacial cycles and climate change on evolutionary timescales. Yet rapid climatic change can compromise the floristic diversity of the tundra, and the ecological and evolutionary changes in the Arctic from anthropogenic forces remain understudied. In this review, we synthesize knowledge of Arctic floral biodiversity across the entirety of the region within the context of its climatic history. We present critical gaps and challenges in modeling and documenting the consequences of anthropogenic changes for Arctic flora, informed by data from the Late Quaternary (~20 ka). We found that previous forecasts of Arctic plant responses to climate change indicate widespread reductions in habitable area with increasing shrub growth and abundance as a function of annual temperature increase. Such shifts in the distribution and composition of extant Arctic flora will likely increase with global climate through changes to the carbon cycle, necessitating a unified global effort in conserving these plants. More data and research on the continuity of tundra communities are needed to firmly assess the risk climate change poses to the Arctic. 

Structural batteries, also known as “massless batteries”, integrate energy storage directly into load-bearing materials, offering a transformative alternative to traditional Li-ion batteries. Unlike conventional systems that serve only as energy storage devices, structural batteries replace passive structural components, reducing overall weight while providing mechanical reinforcement. However, achieving uniform and efficient coatings of active materials on carbon fibers remains a major challenge, limiting their scalability and electrochemical performance. This study investigates ultrasonic spray coating as a precise and scalable technique for fabricating composite cathodes in structural batteries. Using a computer-controlled ultrasonic nozzle, this method ensures uniform deposition with minimal material waste while maintaining the mechanical integrity of carbon fibers. Compared to traditional techniques such as electrophoretic deposition, vacuum bag hot plate processing, and dip-coating, ultrasonic spray coating achieved superior coating consistency and reproducibility. Electrochemical testing revealed a specific capacity of 100 mAh/gLFP with 80% retention for more than 350 cycles at 0.5 C, demonstrating its potential as a viable coating solution. While structural batteries are not yet commercially viable, these findings represent a step toward their practical implementation. Further research and optimization will be essential in advancing this technology for next-generation aerospace and transportation applications. 

In collaborative systems, both technical and social factors influence decisions. While collaborative options may yield desired outcomes, a lack of understanding between parties can hinder collaboration. Effective communication facilitates information exchange and comprehension of partners' intentions, guiding designers toward collaborative decisions. This study examines the impact of a communication channel designed to share actors' collaboration intentions on the accuracy of information exchange and strategic decisions in a collaborative design process. The research uses secondary data from a human experiment involving a collaborative system design problem to assess the intervention's effects. The experimental procedure involves actors completing 30 paired tasks, earning or losing points based on joint decisions with their partners. Participants represent decision-makers from different car manufacturing companies. The experimental data includes 28 junior-year plus STEM undergraduate and graduate students completing paired decision-making collaborative tasks allowed to exchange verbal information and have an additional communication channel to share intentions. The usage of the communication channel is investigated using multiple statistical tests. Results indicate that actors share their intentions accurately and honestly via the communication channel. Even in inaccurate cases, actors’ decisions shift significantly due to their partner's reported strategic intentions. This research underscores the importance of communication for better management of collaborative systems.