Examining the efficacy of vibrotactile displays for monitoring patient vital signs: Six laboratory studies of change detection and state identification.

Healthcare workers often monitor patients while moving between different locations and tasks, and away from conventional monitoring displays. Vibrotactile displays can provide patient information in vibrotactile patterns that are felt regardless of the worker's location. We examined how effectively participants could identify changes in vibrotactile representations of patient heart rate (HR) and oxygen saturation (SpO2). In Experiment 1, participants identified changes in HR and SpO2 with greater than 90% accuracy while using vibrotactile displays configured in either an integrated or a separated format. In Experiment 2, incidental auditory and visual cues were removed and performance was still greater than 90% for the integrated display. In Experiments 3 and 4, ongoing tasks with low or high task load were introduced; high load worsened participants' response accuracy and speed at identifying vital signs. In Experiments 5 and 6, alternative designs were tested, including a design with a seemingly more natural mapping of HR to vibrotactile stimulation. However, no design supported more accurate performance than the integrated display. Results are interpreted with respect to multiple resource theory, and constraints on conforming to design guidelines are noted. Vibrotactile displays appear to be viable and therefore potentially suitable for use in healthcare and other contexts. (PsycInfo Database Record (c) 2022 APA, all rights reserved).

Progressive aridification in East Africa over the last half million years and implications for human evolution.

Evidence for Quaternary climate change in East Africa has been derived from outcrops on land and lake cores and from marine dust, leaf wax, and pollen records. These data have previously been used to evaluate the impact of climate change on hominin evolution, but correlations have proved to be difficult, given poor data continuity and the great distances between marine cores and terrestrial basins where fossil evidence is located. Here, we present continental coring evidence for progressive aridification since about 575 thousand years before present (ka), based on Lake Magadi (Kenya) sediments. This long-term drying trend was interrupted by many wet-dry cycles, with the greatest variability developing during times of high eccentricity-modulated precession. Intense aridification apparent in the Magadi record took place between 525 and 400 ka, with relatively persistent arid conditions after 350 ka and through to the present. Arid conditions in the Magadi Basin coincide with the Mid-Brunhes Event and overlap with mammalian extinctions in the South Kenya Rift between 500 and 400 ka. The 525 to 400 ka arid phase developed in the South Kenya Rift between the period when the last Acheulean tools are reported (at about 500 ka) and before the appearance of Middle Stone Age artifacts (by about 320 ka). Our data suggest that increasing Middle- to Late-Pleistocene aridification and environmental variability may have been drivers in the physical and cultural evolution of Homo sapiens in East Africa.