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Creators/Authors contains: "Clark, Elizabeth"

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  1. Abstract

    Disruptions to education systems (e.g., the COVID‐19 pandemic) evoke a range of responses from teachers. Teachers are required to learn new skills, attend to students' social emotional needs, modify their instructional approaches, and discover innovative ways to engage their students in science, technology, and engineering courses, all while managing their own professional and personal needs. Although teachers of all disciplines adjust their instructional and curricular approaches in response to disruptions, the impetus for this study was to explore the unique challenges of science teachers during the COVID‐19 pandemic that affected their sense of agency (sense of control). To understand how science teachers acquired, used, and invested in capital (i.e., available resources with the potential to meet identified challenges) to achieve professional agency, we studied 113 science teachers in 2020−2021 when they experienced disruptions associated with the pandemic. An analysis of open‐ended responses from 60 teachers indicates that teachers who achieved agency shared four attributes. They (i) demonstrated an awareness of needed capital, (ii) acquired capital, (iii) used capital, and (iv) dedicated effort toward capital‐building for future use. Our findings inform science teacher educators and schools that are committed to mitigating science teacher attrition by understanding how teachers respond to personal and professional stresses.

     
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    Free, publicly-accessible full text available May 1, 2025
  2. null (Ed.)
  3. We propose TuringAdvice, a new challenge task and dataset for language understanding models. Given a written situation that a real person is currently facing, a model must generate helpful advice in natural language. Our evaluation framework tests a fundamental aspect of human language understanding: our ability to use language to resolve open-ended situations by communicating with each other. Empirical results show that today’s models struggle at TuringAdvice, even multibillion parameter models finetuned on 600k in-domain training examples. The best model, T5, writes advice that is at least as helpful as human-written advice in only 14% of cases; a much larger non-finetunable GPT3 model does even worse at 4%. This low performance reveals language understanding errors that are hard to spot outside of a generative setting, showing much room for progress. 
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  4. null (Ed.)
    The locomotion strategies of fossil invertebrates are typically interpreted on the basis of morphological descriptions. However, it has been shown that homologous structures with disparate morphologies in extant invertebrates do not necessarily correlate with differences in their locomotory capability. Here, we present a new methodology for analysing locomotion in fossil invertebrates with a rigid skeleton through an investigation of a cornute stylophoran, an extinct fossil echinoderm with enigmatic morphology that has made its mode of locomotion difficult to reconstruct. We determined the range of motion of a stylophoran arm based on digitized three-dimensional morphology of an early Ordovician form, Phyllocystis crassimarginata . Our analysis showed that efficient arm-forward epifaunal locomotion based on dorsoventral movements, as previously hypothesized for cornute stylophorans, was not possible for this taxon; locomotion driven primarily by lateral movement of the proximal aulacophore was more likely. Three-dimensional digital modelling provides an objective and rigorous methodology for illuminating the movement capabilities and locomotion strategies of fossil invertebrates. 
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  5. Summary

    Lycopodiaceae are one of three surviving families of lycopsids, a lineage of vascular plants with a fossil history dating to at least the Early Devonian or perhaps the Late Silurian (c. 415 Ma). Many fossils have been linked to crown Lycopodiaceae, but the lack of well‐preserved material has hindered definitive recognition of this group in the paleobotanical record.

    New, exceptionally well‐preserved permineralized lycopsid fossils from the Early Cretaceous (125.6 ± 1.0 Ma) of Inner Mongolia, China, were examined in detail using acetate peel and micro‐computed tomography techniques. The anatomy of extant Lycopodiaceae was analyzed for comparison using fluorescence microscopy. Phylogenetic relationships of the new fossil to extant Lycopodiaceae were evaluated using parsimony and maximum likelihood analyses.

    Lycopodicaulis oellgaardiigen. et sp. nov. provides the earliest unequivocal and best‐documented evidence of crown Lycopodiaceae and Lycopodioideae, based on anatomically‐preserved fossil material.

    Recognition ofLycopodicaulisin Asia during the Early Cretaceous indicates the presence of crown Lycopodiaceae at this time, and striking similarities of stem anatomy with extant species provide a framework for the understanding of the interaction of branching and vascular anatomy in crown‐group lycopsids.

     
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