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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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Electrode-electrolytic paste system for space flight electroencephalogram, electrocardiogram, and respiration monitoring systems
Astronaut performance during Gemini extravehicular activities, noting heart and respiration rates and other medical aspects and analyzing workload
Mediation hypothesis for explaining operant reinforcement effect on skeletally mediated autonomic response, noting uncoupling of GSR and deep respiration response
Analog-to-digital computer accepts physiological flight data as three basic analog input signals - the ECG signal, the flowmeter signal which is a respiration monitor, and the accelerometer signal which measures the normal-g-load on the subject.
Reflexes and control of respiration and oxygen circulation in human body
Decreased intensity of myocardial respiration and oxygen metabolism as age factors
Tissue respiration and hydrogenase changes in gamma irradiated mice during acceleration
Hamsters responses to helium-oxygen and nitrogen- oxygen at ambient temperatures, comparing respiration rates, weights and body temperatures
Glycolysis control by respiration in human leukocytes with and without Pasteur effect conditions
System collects medical data directly from patients and permanently records and displays several parameters - electrocardiograph, electroencephalograph, heart rate, respiration rate, auscultatory blood pressure, leg circumference changes, body temperature, and time. Components and operation of the system are described.
Ego strength relationship to respiration in response to sound and light simulation tested in subjects balanced for alertness-drowsiness by EEG criteria
Sheep cardiac rate, respiration rate, hematocrit, erythrocytes per cubic mm and hemoglobin concentration responses to elevated ambient carbon dioxide
Flowmeters for sensing low fluid flow rate and pressure for application to respiration rate studies
Mathematical models used to study complex physiological control systems are discussed. Efforts were made to modify a model of the cardiovascular system for use in studying lower body negative pressure. A computer program was written which allows orderly, straightforward expansion to include exercise, metabolism (thermal stress), respiration, and other body functions.
Techniques developed to automatically process a large quantity of physiological data obtained during a 1000-flight study are described. To reduce this data reliably, a study program was conducted using physiological data from X-15 flights as a data source for experimenting with signal enhancement and noise elimination techniques. The techniques include an automatic means for counting heart rates, averaging electrocardiogram waveforms, plotting histograms of heart rate versus frequency, and counting respiration rates. These techniques were used to reduce more than 2000 hours of physiological data recorded in flight.
An objective method of assessing information workload based on physiological measurements was developed. Information workload, or reserve capacity, was measured using a visual discrimination secondary task and subjective rating of task difficulty. The primary task was two axis (pitch and roll) tracking, and the independent variables in this study were aircraft pitch dynamics and wind gust disturbances. The study was structured to provide: (1) a sensitive, nonloading measure of reserve capacity, and (2) an unencumbering reliable measurement of the psychophysiological state. From these, a measured workload index (MWI) and physiological workload index (PWI) were extracted. An important measure of the success of this study was the degree to which the MWI and PWI agreed across the 243 randomly-presented, four-minute trials (9 subjects X 9 tasks X 3 replications). The electrophysiological data collected included vectorcardiogaram, respiration, electromyogram, skin impedance, and electroencephalogram. Special computer programs were created for the analysis of each physiological variable. The digital data base then consisted of 82 physiological features for each of the 243 trials. A prediction of workload based on physiological observations was formulated as a simultaneous least-squares prediction problem. A best subset of 10 features was chosen to predict the three measures of reserve capacity. The cannonical correlation coefficient was .754 with a chi squared value of 91.3 which allows rejection of the null hypothesis with p of .995.
The design and manufacture of a respirometer for measuring the oxygen consumption rate of a respiring potato sprout in a Skylab experiment is reported. The device monitors low gravity effects on the biorhythmicity of organisms during space flight. Several experimental runs using bench mounted flight hardware units were inconclusive due to room temperature induced artifacts.
Low concentration effects of CO2 on metabolic respiration and circulation were measured during work and at rest. The relationship between heart rate and metabolic rate is examined, as well as calibration procedures, and rate measurement during submaximal and standard exercise tests. Alterations in acid base and electrolytes were found during exhaustive exercise, including changes in ECG and metabolic alkalosis effects.