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Broadband radio waves emitted from pulsars are distorted and delayed as they propagate toward the Earth due to interactions with the free electrons that compose the interstellar medium (ISM), with lower radio frequencies being more impacted than higher frequencies. Multipath propagation in the ISM results in both later times of arrival for the lower frequencies and causes the observed pulse to arrive with a broadened tail described via the pulse broadening function. We employ the CLEAN deconvolution technique to recover the pulse broadening timescale and by proxy the intrinsic pulse shape. This work expands upon previous descriptions of CLEAN deconvolution used in pulse broadening analyses by parameterizing the efficacy on simulated data and developing a suite of tests to establish which of a set of figures of merit leads to an automatic and consistent determination of the scattering timescale and its uncertainty. We compare our algorithm to the cyclic spectroscopy method of estimating the scattering timescale, specifically to the simulations performed in Dolch et al. (2021). We test our improved algorithm on the highly scattered millisecond pulsar J1903+0327, showing the scattering timescale to change over years, consistent with estimates of the refractive timescale of the pulsar.

 

The molecular complexes described herein use main‐group elements or transition metals to control the stoichiometric cleavage of N−H bonds of ammonia (NH₃) and/or catalyze chemical and electrochemical NH₃oxidation to dinitrogen (N₂). We highlight the phenomenon of coordination‐induced bond weakening and a variety of N−H bond cleavage mechanisms of NH₃including H atom abstraction, inter‐ and intra‐molecular deprotonation reactions, oxidative addition, andσ‐bond metathesis that have been demonstrated with molecular systems. We provide an overview of the molecular complexes reported for the rapidly developing field of NH₃oxidation catalysis to form N₂. These systems exhibit several diverse structure types and innovative ligands to support transition metals capable of activating NH₃and mediating a challenging chemical transformation that requires breaking strong N−H bonds and forming an N−N bond en route to N₂formation.

 

Members of advantaged groups are more likely than members of disadvantaged groups to think, feel, and behave in ways that reinforce their group's position within the hierarchy. This study examined how children's status within a group‐based hierarchy shapes their beliefs about the hierarchy and the groups that comprise it in ways that reinforce the hierarchy. To do this, we randomly assigned children (4–8 years;N = 123; 75 female, 48 male; 21 Asian, 9 Black, 21 Latino/a, 1 Middle‐Eastern/North‐African, 14 multiracial, 41 White, 16 not‐specified) to novel groups that differed in social status (advantaged, disadvantaged, neutral third‐party) and assessed their beliefs about the hierarchy. Across five separate assessments, advantaged‐group children were more likely to judge the hierarchy to be fair, generalizable, and wrong to challenge and were more likely to hold biased intergroup attitudes and exclude disadvantaged group members. In addition, with age, children in both the advantaged‐ and disadvantaged‐groups became more likely to see membership in their own group as inherited, while at the same time expecting group‐relevant behaviors to be determined more by the environment. With age, children also judged the hierarchy to be more unfair and expected the hierarchy to generalize across contexts. These findings provide novel insights into how children's position within hierarchies can contribute to the formation of hierarchy‐reinforcing beliefs.

A total of 123 4–8‐year‐olds were assigned to advantaged, disadvantaged, and third‐party groups within a hierarchy and were assessed on seven hierarchy‐reinforcing beliefs about the hierarchy.

Advantaged children were more likely to say the hierarchy was fair, generalizable, and wrong to challenge and to hold intergroup biases favoring advantaged group members.

With age, advantaged‐ and disadvantaged‐group children held more essentialist beliefs about membership in their own group, but not the behaviors associated with their group.

Results suggest that advantaged group status can shape how children perceive and respond to the hierarchies they are embedded within.

 

We extend results on complex analytic measures on the complex unit circle to a non-commutative multivariate setting. Identifying continuous linear functionals on a certain self-adjoint subspace of the Cuntz–Toeplitz C ∗ - algebra, the free disk operator system, with non-commutative (NC) analogues of complex measures, we refine a previously developed Lebesgue decompo- sition for positive NC measures to establish an NC version of the Frigyes and Marcel Riesz Theorem for “analytic” measures, i.e. complex measures with vanishing positive moments. The proof relies on novel results on the order properties of positive NC measures that we develop and extend from classical measure theory. 

Bacteria harbor diverse mechanisms to defend themselves against their viral predators, bacteriophages. In response, phages can evolve counter-defense systems, most of which are poorly understood. In T4-like phages, the gene tifA prevents bacterial defense by the type III toxin–antitoxin (TA) system toxIN, but the mechanism by which TifA inhibits ToxIN remains unclear. Here, we show that TifA directly binds both the endoribonuclease ToxN and RNA, leading to the formation of a high molecular weight ribonucleoprotein complex in which ToxN is inhibited. The RNA binding activity of TifA is necessary for its interaction with and inhibition of ToxN. Thus, we propose that TifA inhibits ToxN during phage infection by trapping ToxN on cellular RNA, particularly the abundant 16S rRNA, thereby preventing cleavage of phage transcripts. Taken together, our results reveal a novel mechanism underlying inhibition of a phage-defensive RNase toxin by a small, phage-encoded protein.

 

Microbiome science has provided groundbreaking insights into human and animal health. Similarly, evolutionary medicine – the incorporation of eco‐evolutionary concepts into primarily human medical theory and practice – is increasingly recognised for its novel perspectives on modern diseases. Studies of host–microbe relationships have been expanded beyond humans to include a wide range of animal taxa, adding new facets to our understanding of animal ecology, evolution, behaviour, and health. In this review, we propose that a broader application of evolutionary medicine, combined with microbiome science, can provide valuable and innovative perspectives on animal care and conservation. First, we draw on classic ecological principles, such as alternative stable states, to propose an eco‐evolutionary framework for understanding variation in animal microbiomes and their role in animal health and wellbeing. With a focus on mammalian gut microbiomes, we apply this framework to populations of animals under human care, with particular relevance to the many animal species that suffer diseases linked to gut microbial dysfunction (e.g. gut distress and infection, autoimmune disorders, obesity). We discuss diet and microbial landscapes (i.e. the microbes in the animal's external environment), as two factors that are (i) proposed to represent evolutionary mismatches for captive animals, (ii) linked to gut microbiome structure and function, and (iii) potentially best understood from an evolutionary medicine perspective. Keeping within our evolutionary framework, we highlight the potential benefits – and pitfalls – of modern microbial therapies, such as pre‐ and probiotics, faecal microbiota transplants, and microbial rewilding. We discuss the limited, yet growing, empirical evidence for the use of microbial therapies to modulate animal gut microbiomes beneficially. Interspersed throughout, we propose 12 actionable steps, grounded in evolutionary medicine, that can be applied to practical animal care and management. We encourage that these actionable steps be paired with integration of eco‐evolutionary perspectives into our definitions of appropriate animal care standards. The evolutionary perspectives proposed herein may be best appreciated when applied to the broad diversity of species under human care, rather than when solely focused on humans. We urge animal care professionals, veterinarians, nutritionists, scientists, and others to collaborate on these efforts, allowing for simultaneous care of animal patients and the generation of valuable empirical data.