Disturbances in the sleep-wake cycle and circadian rhythms are common symptoms of Alzheimer Disease (AD), and they have generally been considered as late consequences of the neurodegenerative processes. Recent evidence demonstrates that sleep-wake and circadian disruption often occur early in the course of the disease and may even precede the development of cognitive symptoms. Furthermore, the ...

# Graduate Research Assistant, Student Member AIAA * Professor, Associate Fellow AIAA This paper describes initial measurements of the near wake of a 2-bladed teetering, untwisted, squaretipped rotor in forward flight. Issues of periodicity and repeatibility of the core are studied using laser velocimetry and flow-visualization on the front of the rotor wake where cycle to cycle variations are ...

Dijk, Derk-Jan, and Steven W. Lockley. Invited Review: Integration of human sleep-wake regulation and circadian rhythmicity. J Appl Physiol 92: 852–862, 2002; 10.1152/japplphysiol.00924.2001.—The human sleep-wake cycle is generated by a circadian process, originating from the suprachiasmatic nuclei, in interaction with a separate oscillatory process: the sleep homeostat. The sleep-wake cycle is...

Recent advances in sleep neurobiology have allowed development of physiologically based mathematical models of sleep regulation that account for the neuronal dynamics responsible for the regulation of sleep-wake cycles and allow detailed examination of the underlying mechanisms. Neuronal systems in general, and those involved in sleep regulation in particular, are noisy and heterogeneous by the...

THE LAST DECADES HAVE WITNESSED an upsurge of neuropeptide research. These substances regulate or influence various functions like appetite, water intake, learning and memory, adaptive responses to environmental stress, thermoregulation and fever, social behavior, and sleep. One function may be affected by several peptides, and a single peptide can be involved in different functions—a general a...