In 2020, the U.S. government, like other countries, instated a nationwide quarantine to reduce the spread of COVID-19, which had reached pandemic status. Though challenging on a number of levels, the quarantine also provided a unique opportunity to examine the effects of a cultural phenomenon that reduced access to many sources of reinforcement and the potential impact on behavior and health. From a behavioral economic standpoint, the quarantine likely resulted in greater consumption of reinforcers that were highly available in the home, such as social media, sleep, substances, and food, while lowering consumption of reinforcers that were restricted by quarantine policies. These two trends likely combined into a net reduction in the diversity of reinforcers that were available to individuals during the quarantine. For some individuals, these shifts in consumption also predicted changes in health and mental health status, especially those involving consumption of social media, sleep, substances, and food. We discuss the implications for health and mental health associated with these trends and end by offering suggestions on how a more careful programming of available reinforcers during times of low reinforcer diversity may prevent excessive consumption of reinforcers that may affect health or mental health risks.
Rangelands cover over 50% of the land surface area in the western United States, providing important economic, social, and environmental benefits. The resilience of western rangelands, however, is increasingly threatened by climate change impacts. Although climate skepticism among agricultural producers is often cited as a barrier to adaptation, emerging evidence suggests that producers adapt regardless of climate beliefs. This raises critical questions about the relationship between climate beliefs and adaptive behavior. To investigate this relationship, we conducted semistructured interviews with 23 ranchers in Idaho, Montana, and Oregon to examine how they perceive, experience, and adapt to climate change. We found that ranchers' understanding of climate change is more complex than a binary belief in or rejection of climate change. Most ranchers doubted anthropogenic climate change yet described detailed observations of a changing climate. Ranchers adopted a range of adaptation strategies but did not attribute these behaviors to climate change. We identified recurring themes, including climate politicization, regulatory fear and perceived powerlessness, and reframing of responsibility, that illustrate the sociopolitical context shaping these seemingly contradictory positions. Climate skepticism may function as a mechanism for managing dissonance, allowing ranchers to reconcile personal observations of environmental change with dominant community beliefs while preserving their personal identity. Our findings challenge binary framings of belief and behavior and highlight the need for culturally grounded climate communication strategies. We recommend investments in localized climate services, coproduced policies, and outreach that emphasize the cobenefits of adaptation and risk management while aligning with ranchers' values and identities. SIGNIFICANCE STATEMENT: Ranchers steward much of the working lands in the American West, making their decisions central to rangeland resilience under climate change. Our study examines how climate beliefs relate to adaptation and which social factors shape responses. Interviews conducted in Idaho, Montana, and Oregon show that while many ranchers doubt human-caused climate change, they describe shifting seasons and adapt in multiple ways. In practice, climate change adaptation often occurs independent of beliefs and is filtered through politicization, regulatory fear, and moral obligations of land stewardship; risk management is rarely ascribed to climate change. Our findings demonstrate that climate skepticism does not preclude action but instead reflects cultural and political pressures shaping how ranchers engage with climate change. Future research should examine which communication strategies and codesigned climate adaptation policies aligned with ranchers' values and identities can effectively sustain adaptation.
Ammonia (NH3) is widely recognized as a carbon-free energy carrier and an alternative to conventional hydrocarbons for green energy applications; however, its use is often constrained by the challenge of nitrogen oxide (NOx) emissions. Laser-assisted ignition offers precise, non-intrusive control and is investigated in this study as an effective strategy to address the inherent ignition challenges of ammonia-based fuels. A dual-pulse laser ignition system is applied to quantify its effect on instantaneous stretched laminar flame speed (SL) and its role in improving ignition stability and NOx control in ammonia combustion. Instantaneous stretched laminar flame speeds (SL) were evaluated using quasi-direct numerical simulations (DNS) with the Stagni ammonia reaction mechanism over equivalence ratios of phi = 0.7-1.25 and pressure ranging from 0.1 to 0.5 MPa, while assessing the effect of hydrogen addition and the initial degree of preionization. The Damkohler (Da) and Karlovitz (Ka) numbers were calculated to quantify the correlation between chemical time scales and flow-induced stretch effects. The laminar flame speed is evaluated using the radius evolution technique, which tracks the temporal growth of the flame front. To investigate the influence of dual-pulse laser ignition on SL, two modeling approaches are implemented. The first method is the DNS analysis, where SL was estimated using the radius evolution technique; however, this method is computationally intensive. The second approach is proposed to provide an efficient way to estimate the laminar flame speed by coupling the initial DNS results obtained from the plasma solver with the detailed chemistry solver. The quasi-DNS model was validated against available experimental measurements and reference data from the literature. The findings reveal that Laser plasma ignition enhances SL and suppresses NOx emissions relative to conventional ignition process for both pure ammonia and hydrogen-blended ammonia mixtures.
Social technology use can increase access and opportunities for social engagement, yet little is known about how these associations vary across racial/ethnic groups in late life. This study aimed to examine associations between social technology use and social engagement within each racial and ethnic group. Using data from the 2015 National Health and Aging Trends Study (N = 5,648), we conducted survey-weighted logistic regression analyses separately for non-Hispanic Whites (N = 4,147), non-Hispanic Blacks (N = 1,165), and Hispanics (N = 312). Non-Hispanic Whites reported the highest levels of social technology use and social engagement, but distinct social technology-social engagement patterns emerged within each racial/ethnic group. For both non-Hispanic Whites and non-Hispanic Blacks, email/texting was positively associated with visiting family/friends, going out for enjoyment, and attending clubs/organized activities. SNS use was positively associated with visiting family/friends and attending clubs/organized activities for non-Hispanic Whites, but with volunteering for Hispanics. These differential associations suggest that targeted interventions should consider group-specific preferences for social technology types and social activities, as they may reflect cultural, linguistic, or access-related differences. Future research exploring barriers to and opportunities for social technology use across racial/ethnic groups may help develop effective and inclusive interventions for older adults.
The purpose of this article is to explore how andragogical principles can inform instructional decisions and support adult learners' critical engagement with GenAI as a site of methodological inquiry in graduate qualitative research class. It highlights how instructors can use andragogical principles to raise learners' awareness and readiness related to GenAI, facilitate experiential learning activities involving GenAI tools across different stages of the research process, and encourage critical reflection on positionality and subjectivity. It demonstrates how adult learning principles can guide meaningful engagement with GenAI, moving beyond tool adoption to include critical reflection on ethical and epistemological concerns.
