Bart I. Verheyden

Learn More
Haemodynamic responses during parabolic flight were studied. The hypothesis that haemodynamic changes may be counteracted by a transient vagal reflex during acute gravity transitions was tested. ECG, arterial pressure and respiration were recorded continuously in seven male subjects during parabolic flight. Beat-to-beat haemodynamic parameters were(More)
In recent years more studies are using nonlinear dynamics to describe cardiovascular control. Because of the large dispersion of physiological data, it is important to have large studies with both male and female participants to establish a range of physiological healthy values. This study investigated the effect of gender and age on nonlinear indexes.(More)
To what extent does going to space affect cardiovascular function? Although many studies have addressed this question, the answer remains controversial. Even for such primary parameters as heart rate (HR) and blood pressure (BP) contradictory results have been presented. The purpose of this investigation was to evaluate HR and arterial BP in 11 male(More)
BACKGROUND In northern Europe, bluetongue (BT) caused by the BT virus (BTV), serotype 8, was first notified in August 2006 and numerous ruminant herds were affected in 2007 and 2008. However, the origin and the time and place of the original introduction have not yet been determined. METHODS AND PRINCIPAL FINDINGS Four retrospective epidemiological(More)
The precision of subtyping assays is a matter of importance and debate for epidemiologic and, recently, forensic investigations. Strain identity is commonly used to infer a common source even when spatial and temporal data are not congruent. Moreover, the defi nition of a strain is somewhat unclear and relies on analytical methods that vary widely.(More)
OBJECTIVE This study examined the effects of hypnosis on autonomic cardiac control. We hypothesized a modification of autonomic modulation of the heart rate with an enhanced vagal tone during hypnosis compared to baseline. METHODS In 12 healthy subjects (6 men and 6 women, 22.2 +/- 1.0 years of age) ECG was recorded at baseline and during hypnosis. Heart(More)
Heart rate variability (HRV) measurements are used as markers of autonomic modulation of heart rate. Numerical noise titration was applied to a large healthy population to examine the influence of age. Increasing age was associated with decreasing nonlinear behaviour and this age dependency was especially prominent during daytime and was also more(More)
Spaceflight and head-down bed rest (HDBR) can induce the orthostatic intolerance (OI); the mechanisms remain to be clarified. The aim of this study was to determine whether or not OI after HDBR relates to the degree of autonomic cardiovascular adaptation. Fourteen volunteers were enrolled for 60 days of HDBR. A head-up tilt test (HUTT) was performed before(More)
PURPOSE The objective was to investigate autonomic control in groups of European and Chinese astronauts and to identify similarities and differences. METHODS Beat-to-beat heart rate and finger blood pressure, brachial blood pressure, and respiratory frequency were measured from 10 astronauts (five European taking part in three different space missions and(More)
The aim of this study was to evaluate the usefulness of complex demodulation (CDM) in assessing frequency components of heart rate variability (HRV) in the setting of dynamic amplitude variations. First, analysis of simulated data showed that the upper limit of rapid amplitude variations corresponded to a period of less than 16s in order to allow a 95%(More)