Aviat Space Envir Md
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Aviat Space Envir Md · Feb 2009
Review Comparative StudyCivil aviation rules on crew flight time, flight duty, and rest: comparison of 10 ICAO member states.
Members of the International Civil Aviation Organization (ICAO) use various criteria to control flight crew scheduling and rest periods with the intention of reducing fatigue and thus improving airline safety. Comparison of these rules across nations may allow future harmonization of the criteria. ⋯ Although the 10 states in this study have common aims and premises for regulating crew duty, their regulations diverge with respect to details, using different tools in an effort to prevent the occurrence of excessive fatigue in aircrew members.
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Aviat Space Envir Md · Feb 2009
Resting and exercise response to altitude in patients with chronic obstructive pulmonary disease.
Exposure to altitude invariably involves some form of physical activity. There are limited data available to help predict the response to activity at altitude in patients with chronic obstructive pulmonary disease (COPD). The aim of the present study was to investigate the response to acute altitude exposure at rest and during exercise in patients with COPD. ⋯ Baseline arterial oxygen levels and K(CO) are key measures in predicting the hypoxemic response to acute altitude exposure in patients with COPD. The impairment in gas exchange associated with COPD is a significant mechanism causing altitude-related hypoxemia in this group.
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Aviat Space Envir Md · Feb 2009
Spatial disorientation in gondola centrifuges predicted by the form of motion as a whole in 3-D.
During a coordinated turn, subjects can misperceive tilts. Subjects accelerating in tilting-gondola centrifuges without external visual reference underestimate the roll angle, and underestimate more when backward-facing than when forward-facing. In addition, during centrifuge deceleration, the perception of pitch can include tumble while paradoxically maintaining a fixed perceived pitch angle. The goal of the present research was to test two competing hypotheses: 1) that components of motion are perceived relatively independently and then combined to form a three-dimensional (3-D) perception; and 2) that perception is governed by familiarity of motions as a whole in three dimensions, with components depending more strongly on the overall shape of the motion. ⋯ Three-dimensional perception is better predicted by taking into account familiarity with the form of 3-D motion.