Purpose: Many patients suffer a stroke at a significant distance from a specialized center capable of delivering endovascular therapy. As a result, they require rapid transport by helicopter emergency medical services, sometimes while receiving a recombinant tissue plasminogen activator infusion (drip and ship). Despite its critical role in the new era of reperfusion, helicopter emergency medical services remains a poorly evaluated aspect of stroke care. Method: Comprehensive narrative review of all published articles of helicopter emergency medical services related to acute stroke care in the inter-hospital and pre-hospital settings, including technical aspects and physical environment implications. Findings: Helicopter emergency medical services transports are conducted during a critical early time period when specific interventions and ancillary care practices may have a significant influence on outcomes. We have limited knowledge of the potential impact of the unusual physical factors generated by the helicopter on the ischemic brain, which affects our ability to establish rational guidelines for ancillary care and the delivery of specific interventions. Discussion: Unlike the pre-hospital and hospital settings where stroke interventions are delivered, the inter-hospital helicopter emergency medical services transfer setting remains a ''black box'' for acute stroke care and research. This gap is particularly relevant for many patients living in rural areas, or in congested urban areas, that depend on helicopter emergency medical services for rapid access to a tertiary stroke center. Conclusion: Addressing the helicopter emergency medical services stroke gap in clinical trials and acute care delivery would homogenize capabilities through all care settings, thus minimizing potential disparities in research access and outcomes based on geographical location.

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As epitomized in DARPA's 'Augmented Cognition' program, next generation avionics suites are envisioned as sensing, inferring, responding to and ultimately enhancing the cognitive state and capabilities of the pilot. Inferring such complex behavioural states from imagery of the face is a challenging task and multimodal approaches have been favoured for robustness. We have developed and evaluated the feasibility of a system for estimation of cognitive workload levels based on analysis of facial skin temperature. The system is based on thermal infrared imaging of the face, head pose estimation, measurement of the temperature variation across regions of the face and an artificial neural network classifier. The technique was evaluated in a controlled laboratory experiment using subjective measures of workload across tasks as a standard. The system was capable of accurately classifying mental workload into high, medium and low workload levels 81% of the time. The suitability of facial thermography for integration into a multimodal augmented cognition sensor suite is discussed.

Although visual performance was measured in terms of visual response time in many psychophysical studies, such an approach has not been used in evaluating the effect of luminance on traffic sign legibility performance. Traffic sign and retroreflective sign sheeting performance at night have been historically identified with the threshold (farthest) distance for legibility and in many cases from stationary vehicles with no restrictions on viewing time. Because traffic signs are not always read at threshold distances or threshold luminances and because the time available to read traffic signs is usually limited in the real world, a proper assessment of sign legibility performance requires determining information acquisition times above threshold conditions. This study investigated the effect of (legend) luminance and letter size on the information acquisition time and transfer accuracy from simulated traffic signs. Luminances ranged from 3.2 cd/m2 to 80 cd/m2 on positive-contrast textual traffic sign stimuli with contrast ratios of 6:1 and 10:1, positioned at 33 ft/in. and 40 ft/in. legibility indices, and viewed under conditions simulating a nighttime driving environment. The findings suggest that increasing the sign luminance significantly reduces the time to acquire information. Similarly, increasing the sign size (or reducing the legibility index) also reduces the information acquisition time. These findings suggest that larger and brighter signs are more efficient in transferring their message to the driver by reducing information acquisition time, or alternatively, by increasing the transfer accuracy. In return, reduced sign viewing durations and increased reading accuracy are likely to improve roadway safety.