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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 181 records · Page 10
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

The Incidence of Patent Foramen Ovale in 1,000 Consecutive Patients: A Contrast Transesophageal Echocardiography Study

Study objective: Patent foramen ovale (PFO) is present in 10 to 35% of people and has been reported to be an important risk factor for cardioembolic cerebrovascular accidents (CVAs) and transient ischemic attacks (TIAS), especially in younger patients. While contrast transthoracic echocardiography has been used to detect PFO, contrast transesophageal echocardiography (TEE) has a greater sensitivity. Prior studies reported the incidence of PFO in patients presenting with a CVA or TIA. Design: To determine the incidence of PFO in a more general population, we reviewed 1,000 consecutive TEES performed with contrast and color Doppler for the presence of PFO and other cardioembolic risk factors, including atrial septal aneurysm (ASA), aortic plaque, atrial fibrillation (AFib), and atrial thrombi. While imaging with monoplane or biplane TEE, multiple injections of agitated saline solution were injected during cough or Valsalva maneuver to detect flow through a PFO. Patients: There were 482 male and 518 female patients with mean age of 60 + 17 years (range 11 to 93 years). Results: Patent foramen ovale was found in 9.2% of all patients and, though seen in all age groups divided by decade, the incidence in patients aged 40 to 49 years was greater than those aged 70 to 79 years (12.96% vs 6.15%',, p=0.03). Contrast TEE had a much higher detection rate than color Doppler alone. Importantly, there was no greater incidence of PFO in patients with CVA vs thos~ without CVA, or in male vs female patients. Also, there was a very strong correlation between the presence of ASA and PFO (p<.001). Conclusion: Thus, PFO detected by TEE, frequently seen with ASA, is seen in all age groups and does not in itself present a risk factor for CVA. The association of PFO with peripheral thrombosis and CVA needs further study.

Fisher, Daniel C.↗
NASA NTRS2008

Flight, Wind-Tunnel, and Computational Fluid Dynamics Comparison for Cranked Arrow Wing (F-16XL-1) at Subsonic and Transonic Speeds

The data contained on this CD are a supplement to NASA/TP-2001-210629 published in February 2001. This CD replaces a web-site database search and retrieval system - noted as reference 36 in the NASA/TP - that was to supply the aeronautical community with access to the flight data. Unfortunately, this web-site was only available for a short time after the publication of NASA/TP-2001-21068 due to software and support issues. The contents of this CD are organized into five folders containing data from the flight test and reference 1. In particular, the following are provided: (1) tabular data of the Flight Conditions from Table 5; (2) boundary layer data from Table 12 for three flights in multiple formats; (3) skin-friction data - xmgr format (ref. 3) - used to generate Figure 26; (4) surface pressure data with a listing of the parameters; and (5) tuft-images from three cameras in two formats.

John E Lamar↗
NASA NTRS2012

Seasonal and Non-Seasonal Variations of Jupiter's Atmosphere from Observations of Thermal Emission, 1994-2011

We analyzed mid-infrared images of Jupiter's thermal emission, covering approx.1.5 Jovian years, acquired in discrete filters between 7.8 and 24.5 microns. The behavior of stratospheric (approx.10-mbar) and tropospheric (approx.100-400 mbar) temperatures is generally consistent with predictions of seasonal variability, with differences between 100-mbar temperatures +/-50-60deg from the equator on the order of +/-2. Removing this effect, there appear to be long-term quasi-periodic variability of tropospheric temperatures, whose amplitude, phase and period depend on latitude. The behavior of temperatures in the Equatorial Zone (EZ) suggests a approx.4-6-year period with amplitude of about +/-1-1.5 K in temperature. At mid-latitudes, the periodicity is more distinct with amplitudes around +/-1.5-2.5 K and 4-8 year periods. The 4.2-year variation of stratospheric temperatures known as the quasiquadrennial oscillation or "QQO" (Leovy et al. 1991, Nature 354, 380) continued during this period. There were no variations of zonal mean temperatures associated with any of the "global upheaval" events that have produced dramatic changes of jupiter's visible appearance and cloud cover, although there are colder discrete regions associated with updrafts, e.g. the early stages of the re-darkening ("revival") of the South Equatorial Belt (SEB) in late 2010. On the other hand increases in the visible albedos ("fades") of belts are accompanied by increases in the thickness of a 700-mbar cloud layer (most likely NH3 ice) and clouds at higher pressures, together with the mixing ratio of NH3 gas near 400 mbar (above its condensation level). These quantities decrease during re-darkening ("revival") episodes, during which we note discrete features that are exceptions to the general correlation between dark albedos and minimal cloudiness. In contrast to all these changes, the meridional distribution of the 240-mbar para-H2 fraction appears to be invariant in time.

Orton, G.↗
NASA NTRS2016

2016 International Land Model Benchmarking (ILAMB) Workshop Report

As earth system models (ESMs) become increasingly complex, there is a growing need for comprehensive and multi-faceted evaluation of model projections. To advance understanding of terrestrial biogeochemical processes and their interactions with hydrology and climate under conditions of increasing atmospheric carbon dioxide, new analysis methods are required that use observations to constrain model predictions, inform model development, and identify needed measurements and field experiments. Better representations of biogeochemistryclimate feedbacks and ecosystem processes in these models are essential for reducing the acknowledged substantial uncertainties in 21st century climate change projections.

earth system models (ESMs)↗