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Fossils record geological change through time and across space. Conodonts, a group of extinct primitive vertebrates with microscopic feeding elements, were common marine fossils from the Cambrian to the earliest Jurassic. This study focuses on late Paleozoic (uppermost Pennsylvanian-lowermost Permian) conodonts from Kansas and Nebraska. The distribution of these conodonts was strongly influenced by glacial-interglacial cycles of the Late Paleozoic Ice Age, which controlled sea level within the Midcontinent Sea. Samples from units identified as the Americus, Lower Hughes Creek, Upper Hughes Creek, and Bennett cyclothems in each state were processed for conodonts. Elements were identified to species level where possible to characterize the fauna of each unit. This project first tests the correlation of these areas by comparing the faunas. The content and relative abundance of each fauna is compared between the localities (KS vs. NE) and through time at each locality to assess spatial and temporal patterns of change. 

Abstract Microswimmers are self‐propelled particles that navigate fluid environments, offering significant potential for applications in environmental pollutant decomposition, biosensing, and targeted drug delivery. Their performance relies on engineered catalytic surfaces. Gold nanoclusters (AuNCs), with atomically precise structures, tunable optical properties, and high surface area‐to‐volume ratio, provide a new optimal catalyst for enhancing microswimmer propulsion. Unlike bulk gold or nanoparticles, AuNCs may deliver tunable photocatalytic activity and increased catalytic specificity, making them ideal co‐catalysts for hybrid microswimmers. For the first time, this study combines AuNCs with TiO₂/Cr₂O₃Janus microswimmers, combining the unique properties of both materials. This hybrid system capitalizes on the tuned optical properties of AuNCs and their role as co‐catalysts with TiO₂, driving enhanced photocatalytic performance under ultraviolet (UV) excitation. Using motion analysis, it is shown that the AuNC‐microswimmers exhibit significantly greater propulsion and mean squared displacement (MSD) as compared to controls. These findings suggest that the integration of nanoclusters with semiconductor materials enables state of the art, light‐switchable microswimmers. These AuNC‐microswimmer systems may thus offer new opportunities for environmental catalysis and other applications, providing precise control over catalytic and motile behaviors at the microscale. 

As artificial agents proliferate, there will be more and more situations in which they must communicate their capabilities to humans, including what they can “see.” Artificial agents have existed for decades in the form of computer-controlled agents in videogames. We analyze videogames in order to not only inspire the design of better agents, but to stop agent designers from replicating research that has already been theorized, designed, and tested in-depth. We present a qualitative thematic analysis of sight cues in videogames and develop a framework to support human-agent interaction design. The framework identifies the different locations and stimulus types – both visualizations and sonifications – available to designers and the types of information they can convey as sight cues. Insights from several other cue properties are also presented. We close with suggestions for implementing such cues with existing technologies to improve the safety, privacy, and efficiency of human-agent interactions.