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  1. Gardner, Stephanie (Ed.)
    Anxiety can impact overall performance and persistence in college. Student response systems (SRSs), real-time active-learning technologies used to engage students and gauge their understanding, have been shown to elicit anxiety for some students. Kahoot! is an SRS technology that differs from others in that it involves gamification, the use of gamelike elements. Recent studies have explored the impact of active-learning strategies on student anxiety across different institutions, but there is little known about how Kahoot! impacts student perceived anxiety, especially in comparison with other active-learning strategies. In two complementary yet parallel studies of introductory biology courses at a western research-intensive institution ( n = 694) and a southeastern research-intensive institution ( n = 60), we measured students’ perceived anxiety. We then explored how students were influenced by nongraded Kahoot! play and other elements of instruction. Using previously developed and course-specific pre- and post-course surveys, we found students at both universities agreed that nongraded Kahoot! play caused less anxiety compared with other pedagogical practices, such as working in small groups or reading the textbook. After playing Kahoot!, lower-performing students demonstrated greater engagement and lower levels of anxiety compared with their peers, suggesting that Kahoot! may be a particularly engaging active-learning strategy for these students. 
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  2. Abstract

    The contractile protein myosinIIis ubiquitous in muscle. It is widely accepted that animals express tissue‐specific myosin isoforms that differ in amino acid sequence andATPase activity in order to tune muscle contractile velocities. Recent studies, however, suggested that the squidDoryteuthis pealeiimight be an exception; members of this species do not express muscle‐specific myosin isoforms, but instead alter sarcomeric ultrastructure to adjust contractile velocities. We investigated whether this alternative mechanism of tuning muscle contractile velocity is found in other coleoid cephalopods. We analyzed myosin heavy chain transcript sequences and expression profiles from muscular tissues of a cuttlefish,Sepia officinalis, and an octopus,Octopus bimaculoides, to determine if these cephalopods express tissue‐specific myosin heavy chain isoforms. We identified transcripts of four and six different myosin heavy chain isoforms inS. officinalisandO. bimaculoidesmuscular tissues, respectively. Transcripts of all isoforms were expressed in all muscular tissues studied, and thusS. officinalisandO. bimaculoidesdo not appear to express tissue‐specific muscle myosin isoforms. We also examined the sarcomeric ultrastructure in the transverse muscle fibers of the arms ofO. bimaculoidesand the arms and tentacles ofS. officinalisusing transmission electron microscopy and found that the fast contracting fibers of the prey capture tentacles ofS. officinalishave shorter thick filaments than those found in the slower transverse muscle fibers of the arms of both species. It thus appears that coleoid cephalopods, including the cuttlefish and octopus, may use ultrastructural modifications rather than tissue‐specific myosin isoforms to adjust contractile velocities.

     
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