University of Oregon

Receiving support in later life is often experienced as stressful, but for people living with dementia (PLWD) support is an unavoidable necessity for daily functioning. The current study examined the association between receiving support in this unique context and PLWD's hair cortisol, dehydroepiandrosterone (DHEA), and DHEA-to-cortisol ratio, which serve as non-invasive, objective physiological measures that may reflect longer-term HPA-axis activity related to stress. Further, we explored whether caregivers' perspective taking-their ability to understand PLWD's thoughts and feelings-moderated associations between support receipt and hair hormones. Participants included 58 couples managing mild-to-moderate Alzheimer's disease (Mage = 77.60 for PLWD; Mage = 75.48 for caregivers). PLWD self-reported the frequency of emotional and practical support received from their spousal caregivers. Hair samples were collected from the posterior vertex to assess cortisol and DHEA concentrations and were assayed using enzyme immunoassay (EIA) method. Caregivers reported their own perspective taking and both spouses' demographic characteristics. Multiple regressions showed that receiving more frequent emotional support and less frequent practical support from spousal caregivers were associated with higher hair cortisol concentrations in PLWD. Yet, these associations were only evident if caregivers had greater perspective taking. In addition, caregiver perspective taking exacerbated the negative association between receiving emotional support and the DHEA-to-cortisol ratio. By using hair hormones, this study offers preliminary insights into PLWD's stress-related physiological processes in the context of intensive caregiving. Findings refine our understanding of the benefits and costs of caregivers' perspective taking and inform caregiver interventions.

Abstract Research Summary CEO promises are powerful but understudied communication tools. We develop a dual‐mechanism framework theorizing that while CEO promises elevate stakeholder expectations, they simultaneously constrain strategic flexibility. We argue that CEO promise‐making is shaped by two competing pressures: making more promises when the need to manage expectations upward is heightened and fewer promises when the need to preserve flexibility is increased. Further, we predict that under heightened uncertainty, CEOs preserve flexibility through strategic ambiguity (i.e., issuing promises with extended or vague time horizons and lower specificity). Leveraging Large Language Models (LLMs) to analyze over 69,000 earnings‐call transcripts from S&P 1500 firms (2010–2022), we identify 74,017 CEO promises and find support for our predictions. We contribute an original, publicly available dataset of CEO promises. Managerial Summary When CEOs publicly promise positive future results, they shape how investors and analysts view the company. These promises are a double‐edged sword: they can boost investor and stakeholder confidence, but they also lock the company into a pre‐determined path and make later shortfalls or pivots reputationally costly. Analyzing more than 69,000 earnings calls (2010–2022), we find that CEOs make more promises when needing to prove their legitimacy, such as during early tenure, when facing gender bias, or after missing earnings targets. However, in uncertain environments, CEOs often pull back from promise‐making or employ “strategic ambiguity” by making promises with vaguer timelines and details to maintain flexibility. Our analysis suggests that failing to deliver on these public commitments significantly increases the likelihood of CEO dismissal.

In natural environments, animals must effectively maneuver around obstacles to reach goals such as food or shelter. Recent work has demonstrated that laboratory mice use vision for naturalistic behavior such as prey capture, escape, and distance estimation. However, it is unknown to what extent mice use vision relative to other senses such as touch for obstacle avoidance, a critical natural behavior. In this study we developed an obstacle avoidance task in freely moving mice to investigate how vision is used to guide paths around an obstacle obstructing a goal. We found that mice clearly use vision to avoid an obstacle, steering around the obstacle at distances where tactile information isn’t available. By comparing trajectories for mice performing obstacle avoidance in the light versus the dark, we found that vision contributes to more spatially efficient trajectories and paths directed to the open edge of the obstacle. When vision is available, mice make large orienting movements towards the opening of the obstacle at about 10 cm from its edge, suggesting that mice are actively using visual information to direct these movements. Finally, by occluding one eye, we found that mice were still able to avoid obstacles with primarily monocular information. Taken together, these results demonstrate that laboratory mice use vision to avoid an obstacle, taking directed paths that are initiated by large orienting movements. In addition to demonstrating the visual behavioral capabilities of the mouse, this paradigm can serve as a foundation to study the neural circuits that mediate visually guided orienting and locomotion.

Action towards climate change mitigation depends on perceptions of severity. With the digital revolution, climate communication is no longer restricted only to climate experts but it has extended to general public as well. This shift raises a question whether experts and general public equally persuade people about the grave need for climate mitigation. In a dynamic social media setting, fragmented attention and contesting content suits the peripheral route of persuasion, where easily readable, and emotionally appealing prompts often captures attention compared to complicated reasoning based on science. Restricted cognitive elaboration among users with low motivation, leads to heterogenous engagement patterns ranging from critical assessment to responses driven by heuristics, causing asymmetries in climate communication. Hence this study applied Elaboration Likelihood Model (ELM), a type of dual-process theory, on a dataset of climate change tweets to analyse how readability of tweets and complexity of messages (central cues) interact with source credibility (peripheral cues) in shaping users’ engagement on X. Although climate change communication strategies are widely analysed empirical research integrating framing, source expertise and information processing routes in a dynamic social media setting remains restricted. Addressing this gap, the present study aims to examine variations in the readability, engagement, and cognitive framing of climate change discourses on X between experts and general public. Comparing linguistic comprehensibility, user engagement metrics, and shifts in expert communication during important climatic milestones, this study aims to comprehend how message characteristics and source expertise shape public interaction with climate content on social media.This study compares readability scores and engagement metrics (likes, replies, retweets) on an anthropogenic climate change tweets dataset (January 2022 to May 2023) containing 333,635 original tweets. The tweets were clustered into four thematic areas: scientific, anthropogenic, policy, and conspiracy narratives. We found that expert’s tweets were significantly more complicated with lower reading ease score and higher complexity score. Specifically, such observations were reported in anthropogenic, scientific, and conspiracy clusters for experts. No significant variations emerged in the policy cluster, suggesting comparable readability among experts and general public. Cluster-level analyses indicated that expert-authored tweets consistently garner greater engagement compared to tweets by general public. Across all clusters, retweets were found to be higher in the experts’ tweets. Variations in reply are significant only in scientific and policy clusters. Engagement analysis showed experts consistently outperformed the general public, with significantly more likes and retweets, particularly for scientific and policy content. Expertise strongly boosted engagement (peripheral route), while higher reading ease further amplified this effect, especially for experts. Conversely, higher complexity modestly increased engagement overall but reduced the marginal benefit of expertise for likes. Temporal analysis around major climate milestones revealed spikes in expert activity and thematic shifts, with discourse patterns influenced by cognitive biases, including authority bias, confirmation bias, and group polarisation. The results demonstrate that climate communication on social media is shaped by the interaction of source expertise, message accessibility, and cognitive biases, with implications for science communication and public engagement.

We compared freshwater ecosystem management of the Yuba River, in California, USA, and the Noce River in the Province of Trento, Italy to examine how cultural and political practices can shape freshwater ecosystem management strategies within similar geographical and hydrologic contexts. Specifically, we compared climate, land-use history, flow regulation, restoration approaches, and associated challenges and successes. The Yuba and Noce catchments both have Mediterranean climates, runoff sourced by rainfall and glacial or snowmelt, and developed water supply resources for agriculture, municipal water supply, recreation, and power generation. Both rivers have long histories of human modification, including damming in the 20th century to accommodate escalating energy demand and intensive agriculture. Dam releases for power generation on the Noce River result in hydropeaking, altering the eco-morphodynamics and limiting biodiversity. Water supply storage, diversion for agricultural use, and gravel extraction on the Yuba River results in highly altered flow regimes and degraded instream habitat. Contrasts between the rivers’ respective regulatory frameworks and their intended goals yield different management actions. In the Yuba, the US Endangered Species Act drives targeted restoration for species-specific recovery, limiting broader holistic protections for the aquatic ecosystem. Whereas in the Noce, the European Union Water Framework Directive mandates broad ecosystem benchmarks be met, with restoration focused on improving habitat, biodiversity, and water quality. However, the top-down approach may limit stakeholder involvement. Recently, success in coalition building among California water managers, academic institutions, conservation groups, and private landowners has led to reconnecting floodplain habitats and providing environmental flows for native salmonids. Implementing alternative hydropower generation schemes in the Noce has led to improved aquatic biodiversity metrics and increased recreation opportunities. As climate change exacerbates impacted river functions worldwide, comparison of freshwater ecosystem management between international catchments offers potential new solutions for sustaining essential ecosystem services.

The Statewide California Earthquake Center (SCEC) sequence of earthquake and aseismic slip (SEAS) group has regularly developed and published benchmarks along the years to follow recent development in the modeling of sequences of aseismic slip and earthquakes, as well as progress in numerical methods. These benchmarks, as well as the results from the different groups are publicly available at: https://strike.scec.org/cvws/seas/. It provides both reference solutions for code verification and a framework for systematic comparison of different modeling approaches. Every group is welcomed to join this Community driven comparison.Recent efforts have focused on adding physics to better reproduce earthquake cycle by considering 2-dimensional fault (Jiang et al., 2022), improve our understanding of fluid injection processes (Lambert et al., 2025), and the effect of free surface and dipping fault (Erickson et al., 2023).To follow up these developments, the SCEC SEAS group is designing two new benchmarks, that will be released to the community soon:[1] A generalization of our benchmark about fluid injection (BP6) from a 2-dimensional domain to 3-dimensional domain. In this benchmark pore fluid diffuses along a 2-dimensional fault, modifying the effective normal traction through one-way hydromechanical coupling. The fluid is injected for 10 hours on a rate strengthening faut and then shut off. The benchmark is designed to admit an analytical formulation for pore fluid diffusion while avoiding numerical singularities that may occurred with point source injection. For this reason, fluid is injected along a Gaussian profile.[2] An updated version of our previous dipping fault benchmark (BP3), in a two-dimensional medium with a free surface. Previous version assumed that the normal traction along the fault was constant. This is obviously a strong assumption, because the normal traction should increase with depth. However, this has proven to be difficult to simulate numerically as the system is going stiffer with lower normal traction. This benchmark therefore aims at providing a more realistic simulation of a dipping fault with a free surface by introducing depth dependent normal traction while also testing the ability of different numerical code to circumvent the problem of stiffness. This benchmark will be a joint benchmark with CRESCENT (Cascadia Region Earthquake Science Center).This contribution will present the design of these forthcoming benchmarks and will provide an opportunity for the community to discuss about future benchmarks and directions for SEAS code comparison efforts.