A multi-year evaluation of medical student performance on and perceptions of collaborative gross anatomy laboratory examinations.

Collaborative testing and its benefits have been reported in diverse disciplines across different types of academic institutions. However, there has been minimal research conducted on collaborative assessments in medical schools, particularly in the gross anatomy laboratory. The objectives of this study were to explore the effect of collaborative anatomy laboratory examinations on student performance and to gauge student perceptions of this assessment format. This study examined five academic years of medical students' performance on a two-stage, collaborative anatomy laboratory examination wherein each student's overall score was a weighted combination of scores from the individual and team examination. Analyses of a descriptive survey capturing students' perceptions of the assessment method were also performed. Individual examination averages increased since implementing the collaborative assessment (p < 0.001), and team examination averages were higher than individual examination averages (p < 0.001). Teams outperformed each of their team members 98% of the time. Teams had a greater than 0.90 incidence of answering a question correctly if more than one person in the group got the answer correct on the individual portion, and a 0.66 incidence of answering correctly if only one person in their group answered correctly on the individual portion. Student feedback identified the discussions and learning that took place during the team portion to be a beneficial feature of this assessment format. Students also reported that this collaborative assessment made them feel a higher level of responsibility to perform well, and that it improved their understanding of gross anatomy.

Changes in wingstroke kinematics associated with a change in swimming speed in a pteropod mollusk, Clione limacina.

In pteropod mollusks, the gastropod foot has evolved into two broad, wing-like structures that are rhythmically waved through the water for propulsion. The flexibility of the wings lends a tremendous range of motion, an advantage that could be exploited when changing locomotory speed. Here, we investigated the kinematic changes that take place during an increase in swimming speed in the pteropod mollusk Clione limacina. Clione demonstrates two distinct swim speeds: a nearly constant slow swimming behavior and a fast swimming behavior used for escape and hunting. The neural control of Clione's swimming is well documented, as are the neuromuscular changes that bring about Clione's fast swimming. This study examined the kinematics of this swimming behavior at the two speeds. High speed filming was used to obtain 3D data from individuals during both slow and fast swimming. Clione's swimming operates at a low Reynolds number, typically under 200. Within a given swimming speed, we found that wing kinematics are highly consistent from wingbeat to wingbeat, but differ between speeds. The transition to fast swimming sees a significant increase in wing velocity and angle of attack, and range of motion increases as the wings bend more during fast swimming. Clione likely uses a combination of drag-based and unsteady mechanisms for force production at both speeds. The neuromuscular control of Clione's speed change points to a two-gaited swimming behavior, and we consider the kinematic evidence for Clione's swim speeds being discrete gaits.