Eels undulate a larger portion of their bodies while swimming than many other fishes, but the hydrodynamic consequences of this swimming mode are poorly understood. In this study, we examine in detail the hydrodynamics of American eels (Anguilla rostrata) swimming steadily at 1.4 L s(-1) and compare them with previous results from other fishes. We performed high-resolution particle image veloci...

Abstract The thrust producing performance and efficiency of an SD8020 oscillating foil with a symmetrical saw-tooth angle of attack pitching profile was studied through force and torque measurements, as well as dye flow visualization, in the water tunnel at low Reynolds number of 13,000-16,000. The propulsive efficiency and thrust coefficient of the pitching foil were determined as a function o...

Sleep quality has a large impact on daily performance and general health. Among the different methods of objectively measuring sleep quality, actigraphy continues to be very popular. It can take continuous activity measurements over several days in order to determine sleep-wake cycles and calculate sleep variables, including the three standard sleep variables used in determining sleep quality: ...

A number of factors lead to a reduction in airport capacity in weather conditions that prevent the use of visual approach procedures. These factors include a reduction in the number of available runways and the longitudinal wake turbulence separation constraints used by Air Traffic Control (ATC). These wake constraints (table 1) evolved over time to prevent wake encounters in weather conditions...

root class Player extends Objectf bool brave; abstract bool wake() { } ; abstract Weapon kissed() {Player } ; g state class Frog extends Playerf Vocal pouch;bool wake() { } ; abstract Weapon kissed() {Player } ; g state class Frog extends Playerf Vocal pouch; bool wake() { } fpouch.blow() ; braveg Weapon kissed() {Player } fthis⇓Prince; sword:= new Weapong g state class Prince extends Playerf W...

Animals continuously alternate between sleep and wake states throughout their life. The daily organization of sleep and wakefulness is orchestrated by circadian, homeostatic, and motivational processes. Over the last decades, much progress has been made toward determining the neuronal populations involved in sleep/wake regulation. Here, we will discuss how the application of advanced in vivo to...

Introduction: The Moon is an obstruction in the outward flowing solar wind, leaving trailing solar wind plasma void in the anti-sunward direction. This trailing disturbance is called the lunar wake. Solar wind plasma incident on the lunar dayside is absorbed, and the region anti-sunward of the Moon contains a near vacuum, with anomalously low plasma densities. The solar wind eventually fills-in...

BACKGROUND Alteration of the intensity of light reaching the pineal gland through the visual pathway affects the sleepwake cycle in humans. OBJECTIVE To determine the prevalence, types and severity of sleep-wake disorders in the blind and their relation to the degree and cause of blindness. METHODS One hundred and seventy consecutive blind patients were included in the study. The patients w...

Sleep and wakefulness are governed by both the suprachiasmatic nuclei of the hypothalamus (SCN), and a sleep homeostatic process; however, the interaction of these control systems is not well understood. From rodent studies it has been assumed that the SCN promote neither wake nor sleep but gate the homeostatic sleep-promoting process. Yet in humans sleep tendency is lowest during the later wak...

In a recent experiment a wake was created in a two-dimensional lattice of charged dust grains by a charge moving parallel to the lattice plane. Multiple ‘‘Mach cones’’ were observed in the wake. This paper describes a linear theory of the phonon wake caused by a charge moving relative to a crystalline lattice. The theory predicts multiple structures in the wake that are qualitatively similar to...