Abstract Tracking of reference signals is addressed in the context a class nonlinear controlled systems modelled by r -th-order functional differential equations, encompassing inter alia with unknown “control direction” and dead-zone input effects. A control structure developed which ensures that, for every member underlying system admissible signal, tracking error evolves prescribed funnel cho...

Randomly moving but self-propelled agents, such as Escherichia coli bacteria, are expected to fill a volume homogeneously. However, we show that when a population of bacteria is exposed to a microfabricated wall of funnel-shaped openings, the random motion of bacteria through the openings is rectified by tracking (trapping) of the swimming bacteria along the funnel wall. This leads to a buildup...

BACKGROUND Funnel technique is a method used for the insertion of screw into thoracic pedicle. AIM To evaluate the biomechanical characteristics of thoracic pedicle screw placement using the Funnel technique, trying to provide biomechanical basis for clinical application of this technology. METHODS 14 functional spinal units (T6 to T10) were selected from thoracic spine specimens of 14 fres...

The p7 membrane protein encoded by hepatitis C virus (HCV) assembles into a homo-hexamer that selectively conducts cations. An earlier solution NMR structure of the hexameric complex revealed a funnel-like architecture and suggests that a ring of conserved asparagines near the narrow end of the funnel are important for cation interaction. NMR based drug-binding experiments also suggest that rim...