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Introduction: Microgravity in space is known to cause major alterations in the cardiovascular system. Left ventricular ejection time (LVET) can be measured by the time from the onset point of the pressure wave to the incisura of the dicrotic notch. The aim of this study was to simulate microgravity by head-down tilt bedrest (HDT) to examine changes in LVET in female and male subjects. Methods: 24 healthy subjects (16 males and 8 females, height 176 ± 7 cm, weight 77 ± 6 kg, age 37 ± 10 years) were enrolled in a HDT study. The bed rest study applied strict –6° HDT for 60 days. Pulse wave measurements were taken using an oscillometric pressure cuff on the brachial artery. LVET index (LVETi) was calculated according to Weissler et al [1]. LVETis of different measurement times were compared using repeated measures ANOVA with post-hoc analysis using paired t-tests and Bonferroni correction. Results: Figure shows a decrease of LVETi during bed rest, followed by a sharp rise of LVETi after bed rest. Repeated measures ANOVA confirmed significant differences between measurement times. The increase of LVETi from each HDT measurement day to 4 days after HDT (R + 4) was significant (p < 0.001). There were no significant differences comparing male and female subjects. FigureLVETi measured 6 days before (BDC-6), on the 5th day (HDT05), on the 21st day (HDT21), on the 60th day (HDT60), and 4 days after (R + 4) bedrest. Bold red and gray lines indicate female and male mean values. Discussion/Conclusion: Overall, we conclude that LVETi decreased during HDT and reached four days after bed rest a similar level as before for both female and male subjects. As LVETi removes heart rate induced effects on LVET, the change in LVETi might be a result of change in ventricular ejection and afterload.

Albeit a wide range of e-participation platforms being already available, the level of public participation remains low. Governments around the world as well as academia are currently exploring new ways to design participation methods that are more engaging to use and will foster participation. One of the strategies is gamification. By adding game elements to e-participation platforms it is hoped to motivate for citizens to engage. This paper reviewed a large number of e-participation platforms, seeking to provide an overview of the current state of the art of so-called gamified participation initiatives. Our results show that while about half of the review projects can be categorized as game-related, only a small amount employs gamification. Moreover, current gamified participation initiatives seem to focus on reward-based gamification, a strategy which is said to come with risks. In this paper we further provide recommendations for future gamified participation projects.