The Florida Clinical Skills Collaborative: A New Regional Consortium for the Assessment of Clinical Skills.

Discontinuation of the United States Medical Licensing Examination (USMLE) Step 2 Clinical Skills (CS) exam and Comprehensive Osteopathic Medical Licensing Examination (COMLEX) Level 2 Performance Evaluation (2-PE) raised questions about the ability of medical schools to ensure the clinical skills competence of graduating students. In February 2021, representatives from all Florida, United States, allopathic and osteopathic schools initiated a collaboration to address this critically important issue in the evolving landscape of medical education. A 5-point Likert scale survey of all members (n=18/20 individuals representing 10/10 institutions) reveals that initial interest in joining the collaboration was high among both individuals (mean 4.78, SD 0.43) and institutions (mean 4.69, SD 0.48). Most individuals (mean 4.78, SD 0.55) and institutions (mean 4.53, SD 0.72) are highly satisfied with their decision to join. Members most commonly cited a "desire to establish a shared assessment in place of Step 2 CS/2-PE" as their most important reason for joining. Experienced benefits of membership were ranked as the following: 1) Networking, 2) Shared resources for curriculum implementation, 3) Scholarship, and 4) Work towards a shared assessment in place of Step 2 CS/2-PE. Challenges of membership were ranked as the following: 1) Logistics such as scheduling and technology, 2) Agreement on common goals, 3) Total time commitment, and 4) Large group size. Members cited the "administration of a joint assessment pilot" as the highest priority for the coming year. Florida has successfully launched a regional consortium for the assessment of clinical skills competency with high levels of member satisfaction which may serve as a model for future regional consortia.

Detecting substrate engagement: responses of tarsal campaniform sensilla in cockroaches.

Sensory signals of contact and engagement with the substrate are important in the control and adaptation of posture and locomotion. We characterized responses of campaniform sensilla, receptors that encode forces as cuticular strains, in the tarsi (feet) of cockroaches using neurophysiological techniques and digital imaging. A campaniform sensillum on the fourth tarsal segment was readily identified by its large action potential in nerve recordings. The receptor discharged to contractions of the retractor unguis muscle, which engages the pretarsus (claws and arolium) with the substrate. We mimicked the effects of muscle contractions by applying displacements to the retractor apodeme (tendon). Sensillum firing did not occur to unopposed movements, but followed engagement of the claws with an object. Vector analysis of forces suggested that resisted muscle contractions produce counterforces that axially compress the tarsal segments. Close joint packing of tarsal segments was clearly observed following claw engagement. Physiological experiments showed that the sensillum responded vigorously to axial forces applied directly to the distal tarsus. Discharges of tarsal campaniform sensilla could effectively signal active substrate engagement when the pretarsal claws and arolium are used to grip the substrate in climbing, traversing irregular terrains or walking on inverted surfaces.

Neurobiology: reconstructing the neural control of leg coordination.

Walking is adaptable because the timing of movements of individual legs can be varied while maintaining leg coordination. Recent work in stick insects shows that leg coordination set by interactions of pattern generating circuits can be overridden by sensory feedback.

Sensory signals of unloading in one leg follow stance onset in another leg: transfer of load and emergent coordination in cockroach walking.

The transfer of load from one leg to another is an essential component in walking, but sense organs that signal this process have rarely been identified. We used high-speed digital imaging and neurophysiological recordings to characterize activities of tibial campaniform sensilla, receptors that detect forces via cuticular strains, in the middle legs of cockroaches during walking. Previous studies demonstrated that the distal tibial sensilla discharge when body load is suddenly decreased in freely standing animals. Sensory recordings during walking showed that distal receptors in the middle leg fired an intense burst near the end of the stance phase. We tested the hypothesis that initiation of distal firing resulted from the action of other legs entering stance. Analysis of leg movements in slow walking showed that sensory bursts in the middle leg closely followed stance onset of the ipsilateral hind leg while the ipsilateral front leg entered stance earlier in phase. Similar phases of leg movement were found in slow walking in experiments in which animals had no implanted recording wires. Those studies also demonstrated that the opposite middle leg entered stance earlier in phase. Measurements of leg positions in walking showed that the hind leg tarsus was placed closest to the middle leg, in keeping with a "targeting" strategy. Triggering of distal bursts in the middle leg by mechanical action of the hind leg could facilitate the onset of swing in the middle leg through local reflex effects and contribute to emergent coordination of leg movements in metachronal gaits.

Neurobiology: venom of wasps and initiation of movements.

The ability to initiate movements can be impaired in some brain injuries even though motor actions proceed normally once they are begun. The effects of venom that wasps use in preying upon cockroaches could provide insights into this problem.

Tuning posture to body load: decreases in load produce discrete sensory signals in the legs of freely standing cockroaches.

Decreases in load are important cues in the control of posture and walking. We recorded activities of the tibial campaniform sensilla, receptors that monitor forces as strains in the exoskeleton, in the middle legs of freely moving cockroaches. Small magnets were attached to the thorax and body load was changed by applying currents to a coil below the substrate. Body position was monitored by video recording. The tibial sensilla are organized into proximal and distal subgroups that have different response properties and reflex effects: proximal sensilla excite extensor motoneurons while distal receptors inhibit extensor firing. Sudden load decreases elicited bursts from distal sensilla, while increased load excited proximal receptors. The onset of sensory discharges closely approximated the time of peak velocity of body movement in both load decreases and increases. Firing of distal sensilla rapidly adapted to sustained unloading, while proximal sensilla discharged tonically to load increases. Load decreases of small amplitude or at low rates produced only inhibition of proximal activity while decrements of larger size or rate elicited distal firing. These response properties may provide discrete signals that either modulate excitatory extensor drive during small load variations or inhibit support prior to compensatory stepping or initiation of swing.