Experimental identification of a mathematical model of human operator working under mental stress.

In engineering the human is considered as one of the system elements. In most studies, his/her model remains unchanged due to the external factors. The present study shows that a relation between the mental stress and human dynamics cannot be neglected.

Heart rate variability (HRV) during virtual reality immersion.

The goal of the study was assessment of the hour-long training involving handling virtual environment (sVR) and watching a stereoscopic 3D movie on the mechanisms of autonomic heart rate (HR) regulation among the subjects who were not predisposed to motion sickness. In order to exclude predispositions to motion sickness, all the participants (n=19) underwent a Coriolis test. During an exposure to 3D and sVR the ECG signal was continuously recorded using the Holter method.

[Subjective sensations indicating simulator sickness and fatigue after exposure to virtual reality].

Background: The study assessed the incidence and intensity of subjective symptoms indicating simulator sickness among the persons with no inclination to motion sickness, immersed in virtual reality (VR) by watching an hour long movie in the stereoscopic (three-dimensional - 3D) and non-stereoscopic (two-dimensional - 2D) versions and after an hour long training using virtual reality, called sVR.

Material And Methods: The sample comprised 20 healthy young men with no inclination to motion sickness. The participants' subjective sensations, indicating symptoms of simulator sickness were assessed using the questionnaire completed by the participants immediately, 20 min and 24 h following the test.

Heart rate variability (HRV) and muscular system activity (EMG) in cases of crash threat during simulated driving of a passenger car.

Objectives: The aim of the study was to verify whether simultaneous responses from the muscular and circulatory system occur in the driver's body under simulated conditions of a crash threat.

Materials And Methods: The study was carried out in a passenger car driving simulator. The crash was included in the driving test scenario developed in an urban setting.

Heart rate variability and motion sickness during forklift simulator driving.

The goal of the study was to determine the effect of a 1-h hour long forklift truck virtual simulator driving on the mechanism of autonomic heart rate (HR) regulation in operators. The participants were divided into 2 subgroups: subjects with no definite inclination to motion sickness (group A) and subjects with a definite inclination to motion sickness (group B). Holter monitoring of electrocardiogram (ECG) signal was carried out in all subjects during the virtual simulator driving.

Job strain, overtime, life style, and cardiovascular risk in managers and physical workers.

The purpose of the study was to determine the relation between overtime, job strain and life style, and cardiovascular risk (CVR) in 97 managers and 98 physical workers. CVR was measured with the Framingham method. Information about job strain, overtime, life style and extra-occupational activities was obtained with a self-administered questionnaire.

Injured professional drivers in Poland - an analysis of the causes and effects in relation to the time of the road accident.

Introduction: The objective of the paper was to present the results of an analysis of road accidents in professional drivers in Poland, from the point of view of their age, tenure, accident causes and effects in relation to the time of the accidents they were involved in.

Method: Data were obtained from a database of the Central Statistical Office. Accidents recorded in statistical accident cards from 6 consecutive years were analysed.

Cardiovascular stress, energy expenditure and subjective perceived ratings of fire fighters during typical fire suppression and rescue tasks.

The study determined physiological and psychophysical responses to fire fighters' typical activities. Self-reported assessment of the most demanding fire fighting/rescue tasks were collected with a questionnaire. Then 19 voluntary fire fighters performed 3 simulated fire fighting/rescue tasks in protective clothing.

[Characteristics of sleep and locomotor activity in night shift workers].

Shift work and night work in particular, account for numerous disturbances in circadian biological rhythms of physiological activities. Shift workers most frequently complain of sleep disturbances manifested among others by sleep duration and quality, as well as by time of proper sleep and naps. Among methods used for the sleep assessment, subjective tests: sleep value questionnaires and 24-h EEG, are most common, however actigraphy is recently considered to be more useful.