Objective. To assess the fatigue risk is an important challenge in improving flight safety in the aviation industry. The aim of this study was to develop a comprehensive fatigue risk management indicators system and a fatigue questionnaire for Chinese civil aviation pilots. Methods. Participants included 74 civil aviation pilots (all males). They finished the questionnaire in 20 min before a flight mission. Estimation of internal consistency with Cronbach's α and Student's t test as well as Pearson's correlation analysis were the main statistical methods. Results. The results revealed that the fatigue questionnaire had acceptable internal consistency reliability and construct validity; there were significant differences in fatigue scores between international and domestic flight pilots. Also, some international flight pilots, who had taken medications as a sleep aid, had worse sleep quality than those who had not. Long-endurance flights across time zones caused significant differences in circadian rhythm. Conclusions. The fatigue questionnaire can be used to measure Chinese civil aviation pilots’ fatigue, which provides a reference for a fatigue risk management system for civil aviation pilots.

Electrical impedance tomography (EIT) is an emerging imaging technology that has been used to monitor brain injury and detect acute stroke. The time and frequency properties of electrode–skin contact impedance are important for brain EIT because brain EIT measurement is performed over a long period when used to monitor brain injury, and is carried out across a wide range of frequencies when used to detect stroke. To our knowledge, no study has simultaneously investigated the time and frequency properties of both electrode and conductive gel for brain EIT. In this study, the contact impedance of 16 combinations consisting of 4 kinds of clinical electrode and five types of commonly used conductive gel was measured on ten volunteers’ scalp for a period of 1 h at frequencies from 100 Hz to 1 MHz using the two-electrode method. And then the performance of each combination was systematically evaluated in terms of the magnitude of contact impedance, and changes in contact impedance with time and frequency. Results showed that combination of Ag+/Ag+Cl− powder electrode and low viscosity conductive gel performed best overall (Ten 20® in this study); it had a relatively low magnitude of contact impedance and superior performance regarding contact impedance with time (p < 0.05) and frequency (p < 0.05). Experimental results indicates that the combination of Ag+/Ag+Cl− powder electrode and low viscosity conductive gel may be the best choice for brain EIT.

Inhibitory control training (ICT) is a promising method to improve individual performance of inhibitory control (IC). Recent studies have suggested transcutaneous vagus nerve stimulation (tVNS) as a novel approach to affect cognitive function owing to its ability to modulate the locus coeruleus-noradrenaline system. To examine the synergistic effects of combining ICT with tVNS, 58 young males in college were randomly assigned to four groups: ICT + tVNS, ICT + sham tVNS, sham ICT + tVNS, and sham ICT + sham tVNS. Participants were instructed to complete three sessions that comprised pre-training tests, a training session, and post-training tests sequentially. Results showed that the ICT + tVNS group significantly improved training and near-transfer effects on the stop-signal and Go/No-go tasks, and these effects were larger than those of the other groups. However, none of the groups exhibited the far-transfer effect on the color-word Stroop task. These results suggest that tVNS augments the intervention effects of training and similar inhibition tasks to achieve the synergistic effect; however, it does not modulate the effects of non-training tasks and obtain the far-transfer effect. ICT combined with tVNS may be a valuable intervention for improving IC in healthy individuals in certain industries and offers novel research ideas for using tVNS for cognitive improvement.

Objective. Pilots are commonly exposed to some sources of emotional and cognitive stressors, especially for flight cadets, which have an important influence on flight safety. The present study aimed to study the relationship between emotional trait factors, emotional state, mental workload and simulated flight performance (SFP) under an acute psychological stress situation. Methods. Fifty-five undergraduates were included in the study. The Wong and Law emotional intelligence scale (WLEIS), state-trait anxiety inventory (STAI), stress rating questionnaire (SRQ) and National Aeronautics and Space Administration task load index (NASA-TLX) were used as data collection tools. Nine hours of simulated flight training were conducted in a simulator of the Type-6 Primary Trainer (Aviation University Air Force, China). The simulated flight assessment was taken as the acute psychological stressor. Results. SFP was negatively correlated with tensity and state anxiety. Emotional intelligence (EI) indirectly affected the SFP mediated by emotional state and workload, and emotional state had a mediating effect on the relationship between trait anxiety and SFP. Conclusions. The findings indicated that emotional trait factors (EI and trait anxiety) may indirectly affect SFP under an acute psychological stress situation, and emotional state (tensity and state anxiety) and mental workload played an important mediating role.