Fetal leg posture in uncomplicated breech and cephalic pregnancies

Background The objective of our study was to determine differences in prenatal leg posture development between breech and cephalic-born babies. Materials and methods Ten healthy fetuses in breech and ten healthy fetuses in cephalic presentation were observed by means of weekly ultrasounds from 33 weeks gestational age until birth to assess leg posture. Results The breech fetuses showed a clear preference for an extended leg position; they spent significantly more time with their knees in extension than the cephalic fetuses (p<0.001). The cephalic fetuses showed significantly more leg-crossing than the breech fetuses (p<0.01). For both findings, no significant change over time could be observed in either group. Conclusion These findings show that the intra-uterine position does influence the fetal postural and motor development. However, it seems unlikely that intra-uterine movement restriction can solely be held accountable for the observed differences in leg position between breech and cephalic fetuses. © 2008 The Author(s)

Input Devices for DAS

This chapter gives an overview of the requirements for the input devices for driver assistance functions and the resulting design options: The reader is provided with a systematic procedure for designing input devices according to (Kircher JH, Baum E (Hrsg), Mensch-Maschine-Umwelt. Ergonomie für Konstrukteure, Designer, Planer und Arbeitsgestalter (Man-machine environment. Ergonomics for engineers, designers, planners and human factors engineers). Beuth Verlag GmbH, Berlin/Köln, 1986). This procedure will begin with identifying the requirements for driver assistance system (DAS) input devices, then follows an explanation of how which body part (ex. finger, hand, etc.), posture and grip type, for system interactions are determined. Additionally, it supports the selection of input devices and provides guidance of how to avoid accidental and unauthorized input. Finally it helps with the design and geometric integration of the arrangement, the definition of feedback and use direction, travel and resistance and the identification of controls. General recommendations are illustrated through specific examples of hardware, demonstrating how manifold input controls can be. In the last part of the chapter an overview of novel operation concepts is given, most of which are not currently implemented in vehicles, however, are estimated to gain importance in the future