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We describe a matter-wave Sagnac interferometer using Bose condensed atoms confined in a time-orbiting potential trap. Compared to our previous implementation [Moan et al., Phys. Rev. Lett. 124, 120403 (2020)], our new apparatus provides better thermal stability, improved optical access, and reduced trap anharmonicity. The trapping field can be adjusted to compensate for small tilts of the apparatus in gravity. These features enable operation with an effective Sagnac area of 4 mm2 per orbit, and we observe interference with 25% visibility after two orbits at a total interrogation time of 0.6 s. Long-term measurements indicate a phase stability of 0.2 rad or better. 

We present a conversational AI tutor (CAIT) for the purpose of aiding students on middle school math problems. CAIT was created utilizing the CLASS framework, and it is an LLM fine-tuned on Vicuna using a conversational dataset created by prompting ChatGPT using problems and explanations in ASSISTments. CAIT is trained to generate scaffolding questions, provide hints, and correct mistakes on math problems. We find that CAIT identifies 60% of correct answers as correct, generates effective sub-problems 33% of the time, and has a positive sentiment 72% of the time, with the remaining 28% of interactions being neutral. This paper discusses the hurdles to further implementation of CAIT into ASSISTments, namely improved accuracy and efficacy of sub-problems, and establishes CAIT as a proof of concept that the CLASS framework can be applied to create an effective mathematics tutorbot. 

Mammalia are the only living members of the larger clade known as Synapsida, which has a fossil record spanning from 320mya to today. Despite the fact that much of the ecological diversity of mammals has been considered in light of limb morphology, the origin of broader synapsid limb diversity and its influence on ecological diversity has received less attention. Here we present shape analyses of the forelimbs of the multiple fossil synapsid radiations in comparison to a broad sample of extant Mammalia. Previous work by the authors has shown that shape broadly is not informative of specific locomotor ecomorphologies in earliest fossil Synapsida. Considering the broader scientific use of limb morphology in testing for fossil ecomorphologies, we sought to better understand at what juncture in synapsid evolutionary history do limb metrics begin to show utility in ecomorphological analyses. Shape data on humeri and ulnae elements from an extant sample representing known ecomorphologies provided the framework for a comparative study of extinct ecomorphologies, associated specifically with locomotion. We conducted linear and geometric morphometric comparisons between the extant sample and five taxonomic subsampled radiations moving crown-ward along the synapsid lineage. Taxonomic designations were the PermoCarboniferous "pelycosaurs”, both Permian and Triassic therapsids, "Non-mammaliaforme cynodonts”, and "Mammaliaformes”. Results show that many limb ecomorphological metrics commonly used are not effective designators until close to the origin of crown Mammalia, as late as the Jurassic. This brings into question the overall utility of using extant analogues to test for ecological signal in a given tetrapod group's deepest fossil ancestors.