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Cosmological moduli generically come to dominate the energy density of the early universe, and thereby trigger an early matter dominated era. Such non-standard cosmological histories are expected to have profound effects on the evolution and production of axion cold dark matter and dark radiation, as well as their prospects for detection. We consider moduli-axion couplings and investigate the early history of the coupled system, considering closely the evolution of the homogeneous modulus field, the back-reaction from the axion, and the energy densities of the two fields. A particular point of interest is the enhancement of axion production from modulus decay, due to tachyonic and parametric resonant instabilities, and the implications of such production on the cosmological moduli problem, axion dark radiation, and the available parameter space for axion dark matter. Using an effective field theory approach, WKB-based semi-analytical analysis, and detailed numerical estimates of the co-evolution of the system, we evaluate the expected decay efficiency of the modulus to axions. The effects of higher-order operators are studied and implications for UV-complete frameworks such as the Large Volume Scenarios in Type IIB string theory are considered in detail. 

Academic AbstractAdvantaged group allies have multiple motives for supporting equality, raising questions about their sincerity. We draw upon the covariation model of attributions to explain how disadvantaged group members make attributions about whether advantaged group “allies” are sincerely motivated to empower the disadvantaged group. We propose an Attribution-Identity Model of Sincerity (AIMS) which posits that disadvantaged group members view advantaged group members as sincere allies when they support equality in the presence of inhibitory causes and in the absence of facilitative causes, exceed expectations for the advantaged group, and provide support across time and contexts. Furthermore, those who identify strongly with their disadvantaged group and perceive intergroup inequality as illegitimate are most motivated to ascertain the sincerity of advantaged group members’ allyship. AIMS suggests how members of disadvantaged groups seek to maximize benefits and minimize risks of advantaged group members’ allyship. Public AbstractAdvantaged group members (e.g., men, White Americans) can act as allies for disadvantaged groups (e.g., women, Americans belonging to minoritized racial groups), but members of disadvantaged groups sometimes have reason to question whether their motives are sincere. We argue that members of disadvantaged groups view advantaged group allies as more sincere when they support equality when they do not stand to benefit from it and even when they stand to lose. We also argue that members of disadvantaged groups view advantaged group allies as more sincere when their support for equality goes beyond expectations for their advantaged group, consistently over time, and is not limited to particular situations, forms, or contexts. Members of disadvantaged groups like sincere allies, want to work with them, and feel safe around them. Sincere allies also serve as moral exemplars to other members of advantaged groups. 

Scenarios to stabilize global climate and meet international climate agreements require rapid reductions in human carbon dioxide (CO₂) emissions, often augmented by substantial carbon dioxide removal (CDR) from the atmosphere. While some ocean-based removal techniques show potential promise as part of a broader CDR and decarbonization portfolio, no marine approach is ready yet for deployment at scale because of gaps in both scientific and engineering knowledge. Marine CDR spans a wide range of biotic and abiotic methods, with both common and technique-specific limitations. Further targeted research is needed on CDR efficacy, permanence, and additionality as well as on robust validation methods—measurement, monitoring, reporting, and verification—that are essential to demonstrate the safe removal and long-term storage of CO₂. Engineering studies are needed on constraints including scalability, costs, resource inputs, energy demands, and technical readiness. Research on possible co-benefits, ocean acidification effects, environmental and social impacts, and governance is also required. 

An acid-promoted dearomative rearrangement of O-arylhydroxylamines affords 2-aminocyclohexadien-1-ones, which can in turn be reductively quenched for the synthesis of trans-aminoalcohols on a cyclohexadiene core. This method serves as an efficient entry to the pharmaceutically relevant 1-arylcyclohexylamine scaffold in two steps (one purification) from commercially available or readily prepared 2-arylphenols. 

We present here a passive and label-free droplet microfluidic platform to sort cells stepwise by lactate and proton secretion from glycolysis. A technology developed in our lab, Sorting by Interfacial Tension (SIFT), sorts droplets containing single cells into two populations based on pH by using interfacial tension. Cellular glycolysis lowers the pH of droplets through proton secretion, enabling passive selection based on interfacial tension and hence single-cell glycolysis. The SIFT technique is expanded here by exploiting the dynamic droplet acidification from surfactant adsorption that leads to a concurrent increase in interfacial tension. This allows multiple microfabricated rails at different downstream positions to isolate cells with distinct glycolytic levels. The device is used to correlate sorted cells with three levels of glycolysis with a conventional surface marker for T-cell activation. As glycolysis is associated with both disease and cell state, this technology facilitates the sorting and analysis of crucial cell subpopulations for applications in oncology, immunology and immunotherapy. 

Men can make important contributions to gender equality, but a variety of obstacles impede their engagement with feminism. In this article, we propose a self-determination (Ryan & Deci, 2000) approach to supporting men’s feminist engagement. We argue that men are more likely to engage with feminism more consistently and effectively if they internalize feminist goals and incorporate them into their sense of self, that is, if they develop autonomous motivation. We argue further that men are more likely to develop autonomous motivation if their engagement with feminism satisfies basic psychological needs for autonomy, relatedness, and competence. We suggest a variety of strategies to meet these needs, among them: framing feminism as a men’s issue, considering men’s viewpoints and values, portraying feminism as consistent with gender and masculine norms, encouraging positive interactions with feminist women, and presenting other feminist men as role models and mentors. According to bell hooks (1984), “sexism and sexist oppression, they can only be successfully eradicated if men are compelled to assume responsibility for transforming their consciousness and the consciousness of society as a whole” (p. 81). Our article applies the self-determination theory (Ryan & Deci, 2000) to encourage men to do so. (PsycInfo Database Record (c) 2025 APA, all rights reserved) 

Undergraduate algorithms courses are a natural setting for teaching many of the theoretical ideas of parallel computing. Mergesort is a fundamental sequential divide-and- conquer algorithm often analyzed in such courses. In this work, we present a visualization tool to help demonstrate a novel PRAM algorithm for mergesort that is work efficient and has polylogarithmic span. Our implementation uses the Thread-Safe Graphics Library, which has an existing visualization of parallel mergesort. We demonstrate that our proposed algorithm has better work and span than the one currently visualized. 

Although analogical examples can support better understanding of new science concepts, when analogies are included superficially and without explanation they may have unintended negative effects. In this study, simple inclusion of analogies greatly increased the perceived familiarity and predicted understanding of geology concepts. Higher judgements of familiarity and predicted understanding could produce illusions of understanding when reading texts about these concepts.