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Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.
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Clinical Characteristics of Children With Tourette Syndrome With and Without Sleep Disorder
Not Available
When to Sleep? CHT7 Is Critical for Nutrient-Dependent Quiescence in Chlamydomonas
To survive nutrient scarcity, unicellular organisms establish a reversible quiescent state in which cells cease growth and division and switch metabolism to an energy-conserving mode. When nutrients become available again, cells exit from quiescence and resume growth and division. The mechanistic details for the establishment of an effective quiescent state in response to nutrient shortage remain poorly understood in photosynthetic eukaryotes. Takeuchi et al. (2020) studied the nutrient-dependent life cycle transition in a model green microalga, Chlamydomonas (Chlamydomonas reinhardtii), to bridge this knowledge gap.
Sleep Strategy Based on Double DQN Method for Satellite Ground Relay Station
Not Available
Improved predictions of hospital sleep disruption through sound quality metrics.
Abstract not provided.
Optimizing the Potential Utility of Blue-Blocking Glasses for Sleep and Circadian Health
Not provided.
Sound quality metrics for improved prediction of hospital sleep disruption.
Abstract not provided.
Activation of the pituitary-adrenal axis during rapid eye movement sleep in man.
Electrophysiological study of pituitary-adrenal axis activation during rapid eye movement /REMS/ IN human urology patients
Dreaming sleep in man - changes in urine volume and osmolality.
Changes in urine volume and osmolality during rapid eye movement state in man
Electroencephalogram during orbital flight - Evaluation of depth of sleep
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Sleep-wake activity patterns of a Macaca nemestrina monkey during nine days of weightlessness
Biosatellite 3 onboard camera time lapse photography of monkey sleep/wake activity patterns during weightlessness
Hibernation, sleep, and thermogulation
Nerve activity adaptation to hypothermia and the differences in CNS activity during hypothermia are studied on marmots. Thermoregulatory experiments on hibernating animals indicated a sympathetic response.
Filament winding - Waking the sleeping giant
The use of filament winding (FW) in the production of aerospace composite structures is examined. The FW process applies spools of fiber and prepreg tow or prepreg tape to a male mandrel; the process is more efficient and cost effective than metallic construction. The fibers used in FW and the curing process are explained. The reduced storage and fabrication costs that result from FW are discussed. The use of FW to produce a filament-wound case for a solid rocket motor and the substructure and skin of an aircraft fuselage are described. Areas which require further development in order to expand the use of FW are listed and discussed.
Patterns of sleep-wakefulness before and after transmeridian flight in commercial airline pilots
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STS-40 orbital acceleration research experiment flight results during a typical sleep period
The Orbital Acceleration Research Experiment (OARE), an electrostatic accelerometer package with complete on-orbit calibration capabilities, was flown for the first time aboard the Space Shuttle on STS-40. This is also the first time an accelerometer package with nano-g sensitivity and a calibration facility has flown aboard the Space Shuttle. The instrument is designed to measure and record the Space Shuttle aerodynamic acceleration environment from the free molecule flow regime through the rarified flow transition into the hypersonic continuum regime. Because of its sensitivity, the OARE instrument defects aerodynamic behavior of the Space Shuttle while in low-earth orbit. A 2-hour orbital time period on day seven of the mission, when the crew was asleep and other spacecraft activities were at a minimum, was examined. During the flight, a 'trimmed-mean' filter was used to produce high quality, low frequency data which was successfully stored aboard the Space Shuttle in the OARE data storage system. Initial review of the data indicated that, although the expected precision was achieved, some equipment problems occurred resulting in uncertain accuracy. An acceleration model which includes aerodynamic, gravity-gradient, and rotational effects was constructed and compared with flight data. Examination of the model with the flight data shows the instrument to be sensitive to all major expected low frequency acceleration phenomena; however, some erratic instrument bias behavior persists in two axes. In these axes, the OARE data can be made to match a comprehensive atmospheric-aerodynamic model by making bias adjustments and slight linear corrections for drift. The other axis does not exhibit these difficulties and gives good agreement with the acceleration model.
STS-40 orbital acceleration research experiment flight results during a typical sleep period
The Orbital Acceleration Research Experiment (OARE), an electrostatic accelerometer package with complete on-orbit calibration capabilities was flown aboard Shuttle on STS-40. The instrument is designed to measure and record the Shuttle aerodynamic acceleration environment from the free molecule flow regime through the rarefied flow transition into the hypersonic continuum regime. Because of its sensitivity, the OARE instrument detects aerodynamic behavior of the Shuttle while in low-earth orbit. A 2-h orbital time period on day seven of the mission, when the crew was asleep and other spacecraft activities were at a minimum, was examined. Examination of the model with the flight data shows the instrument to be sensitive to all major expected low-frequency acceleration phenomena; however, some erratic instrument bias behavior persists in two axes. In these axes, the OARE data can be made to match a comprehensive atmospheric-aerodynamic model by making bias adjustments and slight liner corrections for drift.
Kinematics of NGC 4826: A sleeping beauty galaxy, not an evil eye
A recent high resolution H I study of the Sab galaxy NGC 4826 (1992) reveals that the sense of rotation of the neutral gas reverses from the inner to the outer disk. The present paper reports on optical spectra at high velocity resolution in four position angles in NGC 4826, which cover the region of the gas reversal and which reveal a high degree of complexity. In the inner disk, which includes the prominent dusty lane, the stars and gas rotate in concert, and the spiral arms trail (for the adopted geometry). Arcs of ionized gas are observed partially encircling the nucleus; expansion velocities reach 400 km/s. At distances just beyond the prominent dust lane, the ionized gas exhibits a rapid, orderly velocity fall and within 500 parsecs it has reversed from 180 km/s prograde to 200 km/s retrograde; it also has a component radial toward the nucleus of over 100 km/s. The stars, however, continue their prograde rotation. Beyond this transition zone, the neutral gas continues its retrograde rotation, stellar velocities are prograde, but the sense of the almost circular arms is not established. Because of its kinematical complexity as well as its proximity, NGC 4826 is an excellent early-type galaxy in which to observe the long term effects of gas acquistion or a galaxy merger on a disk galaxy.