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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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At least 19 records
All sourcesNASA NTRSDOE OSTI
NASA NTRS2003

Is the food-entrainable circadian oscillator in the digestive system?

Food-anticipatory activity (FAA) is the increase in locomotion and core body temperature that precedes a daily scheduled meal. It is driven by a circadian oscillator but is independent of the suprachiasmatic nuclei. Recent results that reveal meal-entrained clock gene expression in rat and mouse peripheral organs raise the intriguing possibility that the digestive system is the site of the feeding-entrained oscillator (FEO) that underlies FAA. We tested this possibility by comparing FAA and Per1 rhythmicity in the digestive system of the Per1-luciferase transgenic rat. First, rats were entrained to daytime restricted feeding (RF, 10 days), then fed ad libitum (AL, 10 days), then food deprived (FD, 2 days). As expected FAA was evident during RF and disappeared during subsequent AL feeding, but returned at the correct phase during deprivation. The phase of Per1 in liver, stomach and colon shifted from a nocturnal to a diurnal peak during RF, but shifted back to nocturnal phase during the subsequent AL and remained nocturnal during food deprivation periods. Second, rats were entrained to two daily meals at zeitgeber time (ZT) 0400 and ZT 1600. FAA to both meals emerged after about 10days of dual RF. However, all tissues studied (all five liver lobes, esophagus, antral stomach, body of stomach, colon) showed entrainment consistent with only the night-time meal. These two results are inconsistent with the hypothesis that FAA arises as an output of rhythms in the gastrointestinal (GI) system. The results also highlight an interesting diversity among peripheral oscillators in their ability to entrain to meals and the direction of the phase shift after RF ends.

Non-NASA Center↗
NASA NTRS1997

Evaluation of an Anaerobic Digestion System for Processing CELSS Crop Residues for Resource Recovery

Three bioreactors, connected in series, were used to process CELSS potato residues for recovery of resources. The first stage was an anaerobic digestor (8 L working volume; cow rumen contents inoculum; fed-batch; 8 day retention time; feed rate 25 gdw/day) that converted 33% of feed (dry weight loss) to CO2 and "volatile fatty acids" (vfa, 83:8:8 mmolar ratio acetic:propionic:butyric). High nitrate-N in the potato residue feed was absent in the anaerobic effluent, with a high portion converted to NH4(+)-N and the remainder unaccounted and probably lost to denitrification and NH4(+) volatilization. Liquid anaerobic effluent was fed to an aerobic, yeast biomass production vessel (2 L volume; Candida ingens inoculum; batch [pellicle] growth; 2 day retention time) where the VFAs and some NH4(+)-N were converted into yeast biomass. Yeast yields accounted for up to 8% of potato residue fed into the anaerobic bioreactor. The third bioreactor (0.5 L liquid working volume; commercial nitrifier inoculum; packed-bed biofilm; continuous yeast effluent feed; recirculating; constant volume; 2 day hydraulic retention time) was used to convert successfully the remaining NH4(+)-N into nitrate-N (preferred form of N for CELSS crop production) and to remove the remaining degradable soluble organic carbon. Effluents from the last two stages were used for partial replenishment of minerals for hydroponic potato production.

Strayer, R. F.↗
NASA NTRS1994

Heat Stress Monitor

The heavy, cumbersome body protection suits worn by members of hazardous materials response teams cause marked elevation of body temperatures, which can reduce effectiveness and lead to heat stress and injury. The CorTemp System, marketed by Human Technologies, Inc., provides the basis for a body temperature monitoring alarm system. Encased in a three-quarter-inch ingestible capsule, the system includes a mini-thermometer, miniature telemetry system, a microbattery and temperature sensor. It makes its way through the digestive system, continuously monitoring temperature. Findings are sent to the recorder by telemetry, and then displayed and stored for transfer to a computer.

Source record↗
NASA NTRS1999

Inflight Medical Events in the Shuttle Program

Since the first launch of the Space Shuttle in 1981, the astronauts and their flight surgeons have dealt with a variety of inflight medical issues. A review will be provided of these issues as well as medications used in the treatment of these medical problems. Detailed medical debriefs are conducted by the flight ,surgeon with the individual crewmembers three days after landing. These debriefs were review for Shuttle flights from 1988 through 1999 to determine the frequency of inflight medical events. Medical events were grouped by ICD category and the frequency of medical events within those categories were reviewed. The ICD category of Symptoms, Signs and Ill-defined Conditions had the most medical events. Facial fullness and headache were the most common complaints within this category. The ICD category of Respiratory System had the next most common medical events with sinus congestion being the most common complaint. This was followed by Digestive System complaints and Nervous System/Sense Organ complaints. A variety of inflight medical events have occurred throughout the Shuttle program. Fortunately, the majority of these problems have been minor and have been well within the capability of the medical equipment flown and the skills of the Crew Medical Officers. Medical ,problems/procedures that are routine on the ground often present unique problems in the space flight environment. It is important that the flight surgeon understand the common medical problems encountered.

Baisden, Denise L.↗
NASA NTRS1994

Applying Virtual Reality to commercial Edutainment

Virtual reality (VR) when defined as a computer generated, immersive, three dimensional graphics environment which provides varying degrees of interactivity, remains an expensive, highly specialized application, yet to find its way into the school, home, or business. As a novel approach to a theme park-type attraction, though, its use can be justified. This paper describes how a virtual reality 'tour of the human digestive system' was created for the Omniplex Science Museum of Oklahoma City, Oklahoma. The customers main objectives were: (1) to educate; (2) to entertain; (3) to draw visitors; and (4) to generate revenue. The 'Edutainment' system ultimately delivered met these goals. As more such systems come into existence the resulting library of licensable programs will greatly reduce development costs to individual institutions.

Grissom, F.↗
NASA NTRS2011

Space Motion Sickness - Analysis of Medical Debriefs Data for Incidence and Treatment

Astronauts use medications for the treatment of a variety of illnesses during space travel. Data mining efforts to assess minor clinical conditions occurring during Shuttle flights STS-1 through STS-94 revealed that space motion sickness (SMS) was the most common ailment during early flight days, occurring in approx.40% of crewmembers, followed by digestive system disturbances (9%) and infectious diseases, which most commonly involved the respiratory or urinary tracts. A more recent analysis of postflight medical debriefs data to examine trends with respect to medication use by astronauts during spaceflights indicated that ~37% of all prescriptions recorded was for pain followed by sleep (22%), SMS (18%), decongestion (14%), and all others (14%). Further analysis revealed that about 150 of 317 crewmembers experienced symptoms of SMS. Nearly all (132 of 150) crewmembers took medication for the treatment of symptoms with a total of 387 doses. Promethazine was taken most often (201 doses); in most cases this resulted in alleviation of symptoms with 130 crewmembers (65%) reporting feeling much or somewhat better. Although fewer total doses of the combination of promethazine and dextroamphetamine (Phen/Dex) were taken (45 doses), slightly more than half of these doses resulted in improvement. The combination of scopolamine and dextroamphetamine (Scop/Dex) was reported to be effective in only 37% of cases, with 36 of 97 total doses resulting in improvement. A higher percentage (24%) of Scop/Dex doses was reported to be ineffective compared with promethazine alone or as Phen/Dex (10% and 7%, respectively). Comparisons of the effectiveness of the different dosage forms of promethazine revealed that intramuscular injection was most effective in alleviating symptoms with 55% feeling much better, 16% feeling somewhat better, and only 7% feeling no effect or worse. Overall, it appears that promethazine alone was used more frequently during flight and was reported effective for the treatment of SMS.

Putcha, Lakshmi↗
NASA NTRS1992

The EUVE proposal database and scheduling system

The proposal database and scheduling system for the Extreme Ultraviolet Explorer will be described. The proposal database has been implemented to take input for approved observations selected by the EUVE Peer Review Panel and output target information suitable for the scheduling system to digest. The scheduling system is a hybrid of the SPIKE program and EUVE software which checks spacecraft constraints, produces a proposed schedule and selects spacecraft orientations with optimal configurations for acquiring star trackers, etc. This system has been used to schedule the In Orbit Calibration activities that took place this summer, following the EUVE launch in early June 1992. The implemented strategy has implications for the selection of approved targets, which have impacted the Peer Review process. In addition, it will be discussed how the proposal database, founded on Sybase, controls the processing of EUVE Guest Observer data.

Christian, C.↗
NASA NTRS1991

USSR Space Life Sciences Digest, issue 29

This is the twenty-ninth issue of NASA's Space Life Sciences Digest. It is a double issue covering two issues of the Soviet Space Biology and Aerospace Medicine Journal. Issue 29 contains abstracts of 60 journal papers or book chapters published in Russian and of three Soviet monographs. Selected abstracts are illustrated with figures and tables from the original. A review of a book on environmental hygiene and a list of papers presented at a Soviet conference on space biology and medicine are also included. The materials in this issue were identified as relevant to 28 areas of space biology and medicine. The areas are: adaptation, aviation medicine, biological rhythms, body fluids, botany, cardiovascular and respiratory systems, developmental biology, digestive system, endocrinology, equipment and instrumentation, genetics, habitability and environment effects, hematology, human performance, immunology, life support systems, mathematical modeling, metabolism, musculoskeletal system, neurophysiology, nutrition, personnel selection, psychology, radiobiology, reproductive system, space biology and medicine, and the economics of space flight.

Stone, Lydia Razran↗
NASA NTRS2003

Multispectral imaging system for contaminant detection

An automated inspection system for detecting digestive contaminants on food items as they are being processed for consumption includes a conveyor for transporting the food items, a light sealed enclosure which surrounds a portion of the conveyor, with a light source and a multispectral or hyperspectral digital imaging camera disposed within the enclosure. Operation of the conveyor, light source and camera are controlled by a central computer unit. Light reflected by the food items within the enclosure is detected in predetermined wavelength bands, and detected intensity values are analyzed to detect the presence of digestive contamination.

Poole, Gavin H.↗
NASA NTRS2009

NASA Tech Briefs, April 2009

Topics covered include: Direct-Solve Image-Based Wavefront Sensing; Use of UV Sources for Detection and Identification of Explosives; Using Fluorescent Viruses for Detecting Bacteria in Water; Gradiometer Using Middle Loops as Sensing Elements in a Low-Field SQUID MRI System; Volcano Monitor: Autonomous Triggering of In-Situ Sensors; Wireless Fluid-Level Sensors for Harsh Environments; Interference-Detection Module in a Digital Radar Receiver; Modal Vibration Analysis of Large Castings; Structural/Radiation-Shielding Epoxies; Integrated Multilayer Insulation; Apparatus for Screening Multiple Oxygen-Reduction Catalysts; Determining Aliasing in Isolated Signal Conditioning Modules; Composite Bipolar Plate for Unitized Fuel Cell/Electrolyzer Systems; Spectrum Analyzers Incorporating Tunable WGM Resonators; Quantum-Well Thermophotovoltaic Cells; Bounded-Angle Iterative Decoding of LDPC Codes; Conversion from Tree to Graph Representation of Requirements; Parallel Hybrid Vehicle Optimal Storage System; and Anaerobic Digestion in a Flooded Densified Leachbed.

Source record↗
NASA NTRS2018

Closed Loop Water Purification System Utilizing an Algae Membrane Photobioreactor for the International Space Station

The International Space Station (ISS) currently operates on an open-loop water purification and distribution system. This system is only 75% efficient with a 25% water loss that must be resupplied on a quarterly basis through cargo resupply missions (Pickett, M.). This system is not feasible for long-duration spaceflight missions. A closed-loop water purification system aboard the ISS can benefit water reclamation and become the water purification system for long-term space flight. The primary sub-systems integrated within the proposed closed loop system include an anaerobic digestion membrane bioreactor and an algae membrane photobioreactor. The processes mimics the abilities of natural biological systems naturally. The water that flows from the algal membrane photobioreactor is rich in nutrients providing a feed source for plants aboard the ISS or can be further processed for potable water.

photobioreactor↗
NASA NTRS1978

Remote sensing data handbook

A digest of information on remote sensor data systems is given. It includes characteristics of spaceborne sensors and the supportive systems immediately associated therewith. It also includes end-to-end systems information that will assist the user in appraising total data system impact produced by a sensor. The objective is to provide a tool for anticipating the complexity of systems and potential data system problems as new user needs are generated. Materials in this handbook span sensor systems from the present to those planned for use in the 1990's. Sensor systems on all planned missions are presented in digest form, condensed from data as available at the time of compilation. Projections are made of anticipated systems.

Source record↗
NASA NTRS1995

Managing Complexity in Multidisciplinary Visualization

As high performance computing technology progresses, computational simulations are becoming more advanced in their capabilities. In the computational aerosciences domain, single discipline steady-state simulations computed on a single grid are far from the state-of-the-art. In their place are complex, time-dependent multidisciplinary simulations that attempt to model a given geometry more realistically. The product of these multidisciplinary simulations is a massive amount of data stored in different formats, grid topologies, units of measure, etc., as a result of the differences in the simulated physical domains. In addition to the challenges posed by setting up and performing the simulation, additional challenges exist in analyzing computational results. Visualization plays an important role in the advancement of multidisciplinary simulations. To date, visualization has been used to aid in the interpretation of large amounts of simulation data. Because the human visual system is effective in digesting a large amount of information presented graphically, visualization has helped simulation scientists to understand complex simulation results. As these simulations become even more complex, integrating several different physical domains, visualization will be critical to digest the massive amount of information. Another important role for visualization is to provide a common communication medium from which the domain scientists can use to develop, debug, and analyze their work. Multidisciplinary analyses are the next step in simulation technology, not only in computational aerosciences, but in many other areas such as global climate modeling. Visualization researchers must understand and work towards the challenges posed by multidisciplinary simulation scenarios. This paper addresses some of these challenges, describing technologies that must be investigated to create a useful visualization analysis tool for domain scientists.

Miceli, Kristina D.↗