In this paper, we consider the time-dependent Born–Oppenheimer approximation (BOA) of a classical quantum molecule involving a possibly large number of nuclei and electrons, described by a Schrödinger equation. In the spirit of Born and Oppenheimer’s original idea, we study quantitatively the approximation of the molecular evolution. We obtain an iterable approximation of the molecular evolution to arbitrary order, and we derive an effective equation for the reduced dynamics involving the nuclei equivalent to the original Schrödinger equation and containing no electron variables. We estimate the coefficients of the new equation and find tractable approximations for the molecular dynamics going beyond the one corresponding to the original Born and Oppenheimer approximation.

Archaeology is not new to public education. However, scholars of archaeology education have noted the lack of a systematic approach to the field in the last two decades. In our case study of the Trowels to Teaching Workshop, a five-day professional development program for Maryland K-12 educators conducted in 2025 through the Baltimore Community Archaeology Lab at Towson University, we offer a model for embedding archaeology education in existing applied archaeology programs in the academy. The workshop combined hands-on field and laboratory training, collaboration with Indigenous representatives from the Piscataway Conoy Tribe and the Pocomoke Indian Nation, and active participation by undergraduate student employees who both learned and taught archaeological skills. Formal pre- and post-assessments demonstrated significant learning gains among participating teachers, including increases in archaeological knowledge, confidence in lesson design, and awareness of descendant perspectives. The outcomes highlight how applied archaeology programs in universities can integrate teacher professional development into existing research, provide undergraduates with transformative teaching experiences, and deepen collaborations with descendant communities.

Breastfeeding is a critical component of infant nutrition, and breastfed infants are less likely to become stunted or obese reducing the risk of non-communicable diseases in adult life. Optimal breastfeeding practices remain a challenge worldwide; as adolescents are the mothers and fathers of tomorrow, integrating DOHaD-informed knowledge into school curricula is called for. However, research indicates adolescents have low awareness of the importance of the first 1000 days of life, only see specific elements as relevant to them, and gender-related differences exist in their comprehension. This study evaluated the impact on adolescents of an in-class presentation on parenting and the benefits of breastfeeding in high schools in 5 African countries. Pre- and post-intervention questionnaires were completed by 345 pupils (182 girls, 163 boys, mean age 17.9 years). Analysis indicated the education session impacted pupils’ perceptions of parenting and changed which aspects of breastfeeding they viewed as most and least interesting. A statistically significant difference was evident between genders on the importance of cost-benefits; more boys saw relevance for fathers that no cost is incurred for formula. Boys also ranked the potential to reduce diabetes healthcare costs in adult life higher than girls. Girls preferentially ranked breastfed babies crying less, being easier to feed at night, and diaper changing being less gross as benefits for fathers. School-based education can engage adolescents and impact knowledge and attitudes about breastfeeding. Awareness of differences in girls’ and boys’ perceptions of relevance will enable educational content to be targeted to attract and inform both genders.

Recent years have witnessed an increase in white Americans’ support for the Great Replacement Theory (GRT), the xenophobic conspiracy theory that posits that political elites are embracing permissive immigration policies to bring in “obedient” voters who will vote for them and who will eventually replace native white citizens. This conspiracy theory has been publicly endorsed by several conservative political figures and prominently featured in conservative media outlets, most notably Fox News. This article uses the American Multiracial Panel Study to investigate whether exposure to Fox News is associated with support for the GRT. We find clear and consistent evidence that whites who receive their political news from Fox News are significantly more likely to support core tenets of the GRT than those who do not. We consider our results as evidence of the continued influence of elite rhetoric on public opinion and the unique impact of Fox News on the nature and origins of white public opinion about immigration and the nation’s demographic future.

Increased occurrence of high melt summers across Arctic ice caps and the Greenland Ice Sheet creates thicker, more numerous ice layers within the near surface snow and firn of their accumulation zones. Ice layers may reduce vertical percolation of surface meltwater, promote lateral runoff, reduce refreezing at depth in underlying snow and firn promoting a positive feedback towards more negative surface mass balance. Despite their significance for ice sheet mass balance, controls on ice layer permeability are poorly understood. Here, we explore ice layer permeability using cold-laboratory snowpack experiments with predefined thermal regimes and ice layer thicknesses. We found that in a cold thermal regime (−3°C), ice layers (5–20 mm thick) within the snowpack are impermeable. Meltwater runs off laterally or ponds and subsequently refreezes within 3 h. With temperate conditions (0°C), meltwater ponds over ice layers (10–60 mm thick) without freezing. Temperate ice layers are permeable over timescales of ∼4 to 18 h. We propose that permeability of refrozen ice layers is primarily a function of thermal regime and that ice layer thickness is a secondary control. Our findings pave the way for improved snow and firn model parameterizations of ice layer permeability and ice sheet mass loss projections.

This article overturns the assumption that early modern ballads include too much godly, moralizing content to be considered part of news culture. It uses a wide range of sixteenth- and seventeenth-century English ballads in print and manuscript to demonstrate that one of the news ballad’s most significant features was the inclusion of providence – the ongoing supernatural workings of God in the material world. Placing these songs in the context of other cheap print genres and drawing on research into the role of religion in everyday life, the article shows that rather than undermining the ballad’s role in news culture, providence defined it. Moreover, the early modern distinction between God’s overall plan and specific examples of his intervention in earthly affairs helps to subdivide the genre into those where providence forms an editorial line and those where providence itself provides the story. This second type has traditionally been seen as godly rather than ‘newsy’. Understanding providence shows that those ballads which have been dismissed as more moralistic than topical in fact shared the most important news people could hear.

We generalize Hopf’s theorem to thermostats: the total thermostat curvature of a thermostat without conjugate points is non-positive and vanishes only if the thermostat curvature is identically zero. We further show that, if the thermostat curvature is zero, then the flow has no conjugate points and the Green bundles collapse almost everywhere. Given a thermostat without conjugate points, we prove that the Green bundles are transverse everywhere if and only if it is projectively Anosov. Finally, we provide an example showing that Hopf’s rigidity theorem on the $2$-torus cannot be extended to thermostats. It is also the first example of a projectively Anosov thermostat which is not Anosov.

Waste management is one of the major environmental challenges of the twenty-first century. This Perspective examines how vegetation dynamics at composting facilities and landfills both reflect and influence anthropogenic environmental change. We define our use of the Anthropocene as a human-dominated epoch that is functionally and stratigraphically distinct from the Holocene, and we argue that waste-derived ecosystems constitute model systems for detecting its signals through technogenic substrates and synanthropic succession. Although composting reduces pressure on landfills, incomplete processing of biowaste can disseminate propagules of invasive plant species. Landfills, shaped by disturbance and altered edaphic regimes, support synanthropic plant assemblages dominated by neophytes that act as bioindicators of leachate stress and other pressures. At the same time, spontaneous vegetation provides functional benefits, including slope stabilization, organic matter accumulation and habitat provision during early successional stages. We bring together information on risks and functions, link ecological criteria to permitting, monitoring and post-closure management pathways, and outline practical considerations for integrating plant-based indicators with geochemical screening. These steps enable ecologically sensitive strategies to be implemented that mitigate biodiversity risks while leveraging succession to improve the resilience of waste-derived landscapes.

Despite years of efforts to combat disinformation, we remain far from a satisfactory set of solutions. The rise of generative AI, which enables the creation of highly credible fake content at scale, suggests that the problem is likely to grow even more severe. Lessons from the recent pandemic also call for a reconsideration of how disinformation should be addressed. This paper proposes a new approach that focuses not only on regulating everyone who spreads false information, but also on those who hold epistemic power – individuals with the capacity to shape what others know or believe. Such a strategy has the potential to move the debate forward, as it avoids the most common objection to disinformation regulation: the fear of widespread censorship. The paper argues that an individual’s epistemic position can justifiably differentiate their legal duties, and that those who possess epistemic power should bear corresponding legal – specifically, criminal – responsibility for the abuse of that power in spreading disinformation.

In 1940, Serge Koussevitzky officially founded the Berkshire Music Center (later known as Tanglewood) and appointed Aaron Copland as head of the faculty. Copland actively participated in the US cultural diplomatic initiative of the Good Neighbor Policy by setting up the conditions for modern Latin American composers to attend the Center. By examining the contribution of modern Latin American art music, especially at Tanglewood, this article reflects on the relationship between music and politics, and shows that musical modernism encompasses a much broader artistic spectrum than previously thought.

This article discusses the grammatical role played by the interpretation of an action as either intentional or accidental. It focuses on two grammatical restrictions that exhibit sensitivity to such interpretation. The first concerns so-called subject obviation, whereby, in many European languages, the subject of the subjunctive clause cannot refer to the same individual as the subject of the matrix clause. For the purpose of this article, an important property of subject obviation is that it is weakened in the case of accidental actions. The second restriction pertains to an aspectual restriction in negative imperatives and desire statements in Slavic, which disallows the perfective aspect in these constructions. As is the case with subject obviation, the aspectual restriction in Slavic is lifted when the action is interpreted as accidental. This article argues for a unified semantic-pragmatic account of the weakening of subject obviation and aspectual restriction. It also shows that this weakening of obviation and of aspectual restriction is part of a larger picture where the interpretation of an action as intentional versus accidental plays a central role.

The political participation of Black women has important consequences for electoral outcomes in the US, yet little is known about whether and how affect (both negative and positive) influences this group’s engagement in American politics. Despite the prevalent stereotype that Black women are “angry,” scholarly exploration of the effects of the emotions of these women is rare. In this paper, we highlight a gap in theories that center on Black women and argue that survey question wording about affect may impact how Black women express positive or negative emotions in relation to their political behavior. Using 2016 and 2020 CMPS data, we find support for our expectations. This project highlights the importance of group-specific, intersectional theories and the potential limitations to our understanding of how affect influences political participation.

The propagation of high-energy X-rays or hot electrons have the potential to alter the initial conditions in experimental target designs, especially at material interfaces, for laser-driven inertial confinement fusion (ICF) and high-energy density (HED) experimental platforms. Hot-electron preheat can drastically modify the initial conditions of experimental targets used to study the deceleration-stage Rayleigh–Taylor instability (RTI) both with and without applied magnetic fields. Therefore, it is necessary to understand and quantify the impact of hot-electron preheat. The hydrodynamic (HD) capabilities in the Ares code are used to study the effects varying levels of preheat can have on RTI evolution. The experimental and computational studies presented in this work demonstrate that at high laser intensities of around or greater than $10^{15} \,\textrm {W}\, \textrm {cm}^{-2}$, there is hot-electron generation from laser plasma instabilities which induces substantial preheat and impacts the morphology of RTI evolution and even inhibits the intended RTI growth such that it is not observable experimentally. The necessity of better quantifying hot-electron induced preheat and mitigating its impact on such high-intensity direct-drive laser experiments in the future is discussed.