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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

3D Printing in Zero-G Experiment, In Space Manufacturing (LPS, 4)

The 3D Printing in Zero‐G Experiment has been an ongoing effort for several years. In June 2014 the technology demonstration 3D printer was launched to the International Space Station. In November 2014 the first 21 parts were manufactured in orbit marking the beginning of a paradigm shift that will allow astronauts to be more self‐sufficient and pave the way to larger scale orbital manufacturing. Prior to launch the 21 parts were built on the ground with the flight unit with the same feedstock. These ground control samples are to be tested alongside the flight samples in order to determine if there is a measurable difference between parts built on the ground vs. parts built in space. As of this writing, testing has not yet commenced. Tests to be performed are structured light scanning for volume and geometric discrepancies, CT scanning for density measurement, destructive testing of mechanical samples, and SEM analysis for inter‐laminar adhesion discrepancies. Additionally, an ABS material characterization was performed on mechanical samples built from the same CAD files as the flight and ground samples on different machine / feedstock combinations. The purpose of this testing was twofold: first to obtain mechanical data in order to have a baseline comparison for the flight and ground samples and second to ascertain if there is a measurable difference between machines and feedstock.

Bean, Quincy↗

Lipopolysaccharide modulation of a CD14-like molecule on porcine alveolar macrophages

Cluster of differentiation antigen 14 (CD14) functions as a receptor for lipopolysaccharide (LPS) LPS-binding protein (LBP) complexes. Because LPS has varying effects on CD14 expression in vitro, we evaluated CD14 expression in response to LPS with a fully differentiated macrophage phenotype, the alveolar macrophage. By using flow microfluorometric analysis and a radioimmunoassay with an anti-human CD14 monoclonal antibody (My4) that cross-reacts with porcine CD14, we found that macrophages stimulated with LPS for 24 h exhibited a two- to fivefold increase in CD14-like antigen compared with unstimulated cells. At low concentrations of LPS, up-regulation of the CD14-like antigen was dependent on serum; at higher concentrations of LPS, serum was not required. In the absence of serum a 10-fold higher dose of LPS (10 ng/ml) was required to increase CD14-like expression. In addition, LPS-induced CD14-like up-regulation correlated with secretion of tumor necrosis factor-alpha, regardless of serum concentration. Blockade with My4 antibody significantly inhibited LPS-induced tumor necrosis factor-alpha secretion at 1 ng/ml of LPS. However, inhibition decreased as we increased the LPS concentration, suggesting the existence of CD14-independent pathways of macrophage activation in response to LPS. Alternatively, My4 may have a lower affinity for the porcine CD14 antigen than LPS, which may have only partially blocked the LPS-LBP binding site at high concentrations of LPS. Therefore, these data suggest that LPS activation of porcine alveolar macrophages for 24 h increased CD14-like receptor expression. The degree of CD14-like up-regulation was related to LPS concentration, however, activation did not require the presence of serum at high concentrations of LPS.

Non-NASA Center↗

Relation of the lunar power system to the SEI program and to landers

The people of Earth will need more than 20,000 billion watts (GWe) of electric power by 2050 for a high level of prosperity. Power needs in the 22nd Century could exceed 100,000 GWe. By 2100 the total quantity of thermal energy used could fully deplete the known inventory (10(exp 7) GWt-Y) of all non-renewable sources on Earth except for deuterium and hydrogen for use in proposed fusion reactors. The labor, capital, and mass of power plants required to produce 1 GWe-Y of energy from present-day power plants is summarized. Fossil and nuclear plants respectively consume 80 to 190 M$ and 12 to 48 M$ of fuel per GWe-Y. The Lunar Power System (LPS) uses solar power bases on the moon to beam electric power to Earth. The LPS in the figure supplies load-following power to rectennas on Earth. Additional solar power conversion units are located across the lunar limb from their respective Earthward transmitting stations. LPS can be augmented by mirrors in polar orbit about the moon. The construction of rectennas on Earth determines the base cost (0.001s$/kWe-H) of LPS power. A manned International Lunar Base (ILB) can accelerate the development of LPS by providing the initial transportation and habitation facilities and base operations. ILB can greatly reduce up front costs and risks by emplacing a moderate scale LPS (1-100 GWe). LPS can accelerate the development of the ILB by providing greater funding than is reasonable to expect for purely scientific research. An international ILB/LPS program can foster world trust and prosperity.

Criswell, David R.↗

Influence of High Aspect Ratio Vessel Cell Culture on TNF-Alpha, Insulin Secretion and Glucose Homeostasis in Pancreatic Islets of Langerhans from Wistar Furth Rats

The present studies were carried out to determine the influence of a ground based microgravity paradigm, utilizing the High Aspect Ratio Vessel (HARV) cell culture upon lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha (TNF-alpha) production of pancreatic islets of Langerhans. An additional aim was to elucidate alterations in insulin secretion and glucose utilization using the HARV low shear, gravity averaged vector, cell culture technique. Islets were isolated (1726 +/- 117, 150 micron islet equivalent units) from Wistar Furth rats and assigned to four treatment groups: 1) HARV, 2) HARV plus LPS, 3) static culture, 4) static culture plus LPS. Following 48 hours of culture, insulin concentration was increased in both HARV and static cultures (p<0.05). Islet medium from HARV and static cultures were assayed for TNF-alpha (L929 cytotoxicity assay) and was measured at selected time points for 48 hours. TNF-alpha was significantly increased in LPS-induced HARV and static cultures, yet the increase was more pronounced in the static culture group (p<0.05). This is a novel observation and indicates that TNF producing cells are present in islets and that LPS stimulates TNF secretion in isolated islets. A decrease in insulin concentration was demonstrated in the islet medium of the LPS stimulated HARV culture (p<0.05). That TNF-alpha is associated with a decreased insulin secretion is intriguing, both as it relates to in-flight investigations, and as it may provide insight into the pathophysiology of Type I and Type 11 diabetes. Glucose concentration in islet medium was lesser throughout the experiment in static cultures, suggesting a decreased reliance upon glucose as a metabolic substrate in the islets cultured in HARVS. In conclusion, the present studies demonstrate alterations in LPS induced TNF-alpha production of pancreatic islets of Langerhans, favoring a lesser TNF production in the microgravity HARV paradigm. Additionally, alterations in fuel homeostasis may be promulgated by HARV culture. The clinical and physiological significance of these observations remains to be determined.

Tobin, Brian W.a↗

Flow Analysis of a Gas Turbine Low- Pressure Subsystem

The NASA Lewis Research Center is coordinating a project to numerically simulate aerodynamic flow in the complete low-pressure subsystem (LPS) of a gas turbine engine. The numerical model solves the three-dimensional Navier-Stokes flow equations through all components within the low-pressure subsystem as well as the external flow around the engine nacelle. The Advanced Ducted Propfan Analysis Code (ADPAC), which is being developed jointly by Allison Engine Company and NASA, is the Navier-Stokes flow code being used for LPS simulation. The majority of the LPS project is being done under a NASA Lewis contract with Allison. Other contributors to the project are NYMA and the University of Toledo. For this project, the Energy Efficient Engine designed by GE Aircraft Engines is being modeled. This engine includes a low-pressure system and a high-pressure system. An inlet, a fan, a booster stage, a bypass duct, a lobed mixer, a low-pressure turbine, and a jet nozzle comprise the low-pressure subsystem within this engine. The tightly coupled flow analysis evaluates aerodynamic interactions between all components of the LPS. The high-pressure core engine of this engine is simulated with a one-dimensional thermodynamic cycle code in order to provide boundary conditions to the detailed LPS model. This core engine consists of a high-pressure compressor, a combustor, and a high-pressure turbine. The three-dimensional LPS flow model is coupled to the one-dimensional core engine model to provide a "hybrid" flow model of the complete gas turbine Energy Efficient Engine. The resulting hybrid engine model evaluates the detailed interaction between the LPS components at design and off-design engine operating conditions while considering the lumped-parameter performance of the core engine.

Veres, Joseph P.↗

Linear polarization sensitivity specifications for space-borne instruments

The radiometric accuracy of space-borne instruments such as radiometers and spectroradiometers which make measurements of the earth and other celestial objects can be compromised by the linear polarization sensitivity (LPS) induced by the optical system. Most of these optical systems contain optical elements whose reflectance or transmission is polarization dependent, such as diffraction gratings, folding and scanning mirrors, dichroic filters, and optical fibers. Optical system incorporating such elements generally display linear polarization sensitivity; different linear polarization states incident with equal radiometric power will be measured as different power levels. If the incident polarization state is unknown, the linear polarization sensitivity cannot be compensated during the data reduction. The light reflected from the earth and other planets and moons is usually partially linearly polarized, but in a random distribution. Thus, to make accurate radiometric measurements of these bodies, a radiometer or spectrometer should have a low level of linear polarization sensitivity. This paper contains a mathematical description of LPS, contains references to systems which have imposed a LPS specification, describes some of the sources of LPS, describes how to model LPS by polarization ray tracing, and discusses methods to reduce the LPS of an optical system.

Maymon, Peter W.↗

Simulated Microgravity Reduces TNF-Alpha Activity, Suppresses Glucose Uptake and Enhances Arginine Flux in Pancreatic Islets of Langerhans

The present studies were designed to determine effects of microgravity upon lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha (TNF - alpha) activity and indices of insulin and fuel homeostasis of pancreatic islets of Langerhans. Islets (1726+/-117,150 u IEU) from Wistar Furth rats were treated as: 1) HARV (High Aspect Ratio Vessel cell culture) , 2) HARV plus LPS 3) static culture, 4) static culture plus LPS TNF-alpha (L929 cytotoxicity assay) was significantly increased in LPS-induced HARV and static cultures, yet the increase was more pronounced in the static culture group (p<0.05). A decrease in insulin concentration was demonstrated in the LPS stimulated HARV culture (p<0.05). We observed a greater glucose concentration and increased disappearance of arginine in islets cultured in HARVs. While nitrogenous compound analysis indicated a ubiquitous reliance upon glutamine in all experimental groups, arginine was converted to ornithine at a two-fold greater rate in the islets cultured in the HARV microgravity paradigm (p<0.05). These studies demonstrate alterations in LPS induced TNF-alpha production of pancreatic islets of Langerhans, favoring a lesser TNF activity in the HARV paradigm. These alterations in fuel homeostasis may be promulgated by gravity averaged cell culture methods or by three dimensional cell assembly.

Tobin, Brian W.↗

Photomorphogenesis and photoassimilation in soybean and sorghum grown under broad spectrum or blue-deficient light sources

The role of blue light in plant growth and development was investigated in soybean (Glycine max [L.] Merr. cv Williams) and sorghum (Sorghum bicolor [L.] Moench. cv Rio) grown under equal photosynthetic photon fluxes (approximately 500 micromoles per square meter per second) from broad spectrum daylight fluorescent or blue-deficient, narrow-band (589 nanometers) low pressure sodium (LPS) lamps. Between 14 and 18 days after sowing, it was possible to relate adaptations in photosynthesis and leaf growth to dry matter accumulation. Soybean development under LPS light was similar in several respects to that of shaded plants, consistent with an important role for blue light photoreceptors in regulation of growth response to irradiance. Thus, soybeans from LPS conditions partitioned relatively more growth to leaves and maintained higher average leaf area ratios (mean LAR) that compensated lower net assimilation rates (mean NAR). Relative growth rates were therefore comparable to plants from daylight fluorescent lamps. Reductions in mean NAR were matched by lower rates of net photosynthesis (A) on an area basis in the major photosynthetic source (first trifoliolate) leaf. Lower A in soybean resulted from reduced leaf dry matter per unit leaf area, but lower A under LPS conditions in sorghum correlated with leaf chlorosis and reduced total nitrogen (not observed in soybean). In spite of a lower A, mean NAR was larger in sorghum from LPS conditions, resulting in significantly greater relative growth rates (mean LAR was approximately equal for both light conditions). Leaf starch accumulation rate was higher for both species and starch content at the end of the dark period was elevated two- and three-fold for sorghum and soybean, respectively, under LPS conditions. Possible relations between starch accumulation, leaf export, and plant growth in response to spectral quality were considered.

NASA Discipline Life Support Systems↗

Altered TNF-Alpha, Glucose, Insulin and Amino Acids in Islets Langerhans Cultured in a Microgravity Model System

The present studies were designed to determine effects of a microgravity model system upon lipopolysaccharide (LPS) stimulated tumor necrosis factor alpha (TNF-alpha) activity and indices of insulin and fuel homeostasis of pancreatic islets of Langerhans. Islets (1726+/-1 17,150 u IEU) from Wistar Furth rats were treated as: 1) HARV (High Aspect Ratio Vessel cell culture) , 2) HARV plus LPS, 3) static culture, 4) static culture plus LPS. TNF-alpha (L929 cytotoxicity assay) was significantly increased in LPS-induced HARV and static cultures, yet the increase was more pronounced in the static culture group (p<0.05). A decrease in insulin concentration was demonstrated in the LPS stimulated HARV culture (p<0.05). We observed a greater glucose concentration and increased disappearance of arginine in islets cultured in HARVs. While nitrogenous compound analysis indicated a ubiquitous reliance upon glutamine in all experimental groups, arginine was converted to ornithine at a two-fold greater rate in the islets cultured in the HARV microgravity model system (p<0.05). These studies demonstrate alterations in LPS induced TNF-alpha production of pancreatic islets of Langerhans, favoring a lesser TNF activity in the HARV. These alterations in fuel homeostasis may be promulgated by gravity averaged cell culture methods or by three dimensional cell assembly.

Tobin, Brian W.↗

Triggered-Lightning Interaction with a Lightning Protective System: Current Distribution and Electromagnetic Environment

A new comprehensive lightning instrumentation system has been designed for Launch Complex 39B (LC3913) at the Kennedy Space Center, Florida. This new instrumentation system includes the synchronized recording of six high-speed video cameras; currents through the nine downconductors of the new lightning protection system for LC3913; four dH/dt, 3-axis measurement stations; and five dE/dt stations composed of two antennas each. A 20:1 scaled down model of the new Lightning Protection System (LPS) of LC39B was built at the International Center for Lightning Research and Testing, Camp Blanding, FL. This scaled down lightning protection system was instrumented with the transient recorders, digitizers, and sensors to be used in the final instrumentation installation at LC3913. The instrumentation used at the ICLRT is also a scaled-down instrumentation of the LC39B instrumentation. The scaled-down LPS was subjected to seven direct lightning strikes and six (four triggered and two natural nearby flashes) in 2010. The following measurements were acquired at the ICLRT: currents through the nine downconductors; two dl-/dt, 3-axis stations, one at the center of the LPS (underneath the catenary wires), and another 40 meters south from the center of the LPS; ten dE/dt stations, nine of them on the perimeter of the LPS and one at the center of the LPS (underneath the catenary wire system); and the incident current. Data from representative events are presented and analyzed in this paper.

Mata, C. T.↗

Summary of 2011 Direct and Nearby Lightning Strikes to Launch Complex 39B, Kennedy Space Center, Florida

A Lightning Protection System (LPS) was designed and built at Launch Complex 39B (LC39B), at the Kennedy Space Center (KSC), Florida in 2009. This LPS was instrumented with comprehensive meteorological and lightning data acquisition systems that were deployed from late 2010 until mid 2011. The first direct strikes to the LPS were recorded in March of 2011, when a limited number of sensors had been activated. The lightning instrumentation system detected a total of 70 nearby strokes and 19 direct strokes to the LPS, 2 of the 19 direct strokes to the LPS had two simultaneous ground attachment points (in both instances one channel terminated on the LPS and the other on the nearby ground). Additionally, there are more unaccounted nearby strokes seen on video records for which limited data was acquired either due to the distance of the stroke or the settings of the data acquisition system. Instrumentation deployment chronological milestones, a summary of lightning strikes (direct and nearby), high speed video frames, downconductor currents, and dH/dt and dE/dt typical waveforms for direct and nearby strokes are presented.

Mata, C.T.↗

Cost comparisons of solar power satellites versus lunar based power systems

A comparison is made between projected electricity costs of an optimized space solar power station (SPS) in GEO and a moon-based SPS (LPS). A single SPS would receive sunlight on an almost uninterruptible basis. The LPS would be illumined 50 percent of the time, thus requiring two stations on opposite sides of the moon as well as three terrestrial rectennas spaced 120 deg apart. The 5 percent efficient LPS cells would be manufactured from lunar materials and built into arrays mounted on tall mounds. The steerable GEO SPS would have 15 percent efficient cells. Construction costs would be significantly lower on the moon, but the total antenna area would need to be two orders of magnitude larger to produce the same output as the SPS. It is estimated that the LPS would therefore deliver 5 GW electricity to earth stations at a cost of 511.3 mills/kW, compared to 46.8 mills/kW from the SPS. It is concluded that lunar materials are suitable for building an SPS, not a LPS.

Kerwin, E. M.↗

Light Spectral Quality Effects on the Growth of Potato (Solanum Tuberosum L.) Nodal Cuttings in Vitro

The effects of light spectral quality on the growth of in vitro nodal cuttings of potato (Solanum tuberosum L.) cultivars Norland, Superior, Kennebec, and Denali were examined. The different light spectra were provided by Vita-Lite fluorescent (VF) (a white light control), blue fluorescent (BF), red fluorescent (RF), low-pressure sodium (LPS), and a combination of low-pressure sodium plus cool-white fluorescent lamps (LPS/CWF). For cultivars, stem lengths after 4 wks were longest under LPS, follow by RF, LPS/CWF, VF, and BF (in descending order). Microscopic studies revealed that cells were shortest when cultured in BF or VF environments, and were longest in RF or LPS lamp environments. The highest number axillary branches occurred on plantlets grown with LPS or LPS/CWF, whereas the lowest number occurred with BF. No leaf or stem edema (callus or gall-like growths) occurred iwth LPS or LPS/cwf lighting, and no edema occurred on cv. Norland plantlets, regardless of lighting. Results suggest that shoot morphologic development of in vitro grown potato plants can be controlled by controlling irradiant spectral quality.

Wilson, Deborah A.↗

Reduced phenylalanine ammonia-lyase and tyrosine ammonia-lyase activities and lignin synthesis in wheat grown under low pressure sodium lamps

Wheat (Triticum aestivum L. cv Fremont) grown in hydroponic culture under 24-hour continuous irradiation at 560 to 580 micromoles per square meter per second from either metalhalide (MH), high pressure sodium (HPS), or low pressure sodium (LPS) lamps reached maturity in 70 days. Grain yields were similar under all three lamps, although LPS-grown plants lodged at maturity. Phenylalanine ammonia-lyase (PAL) and a tyrosine ammonia lyase (TAL) with lesser activity were detected in all extracts of leaf, inflorescence, and stem. Ammonia-lyase activities increased with age of the plant, and plants grown under the LPS lamp displayed PAL and TAL activities lower than wheat cultured under MH and HPS radiation. Greenhouse solar-grown wheat had the highest PAL and TAL activities. Lignin content of LPS-grown wheat was also significantly reduced from that of plants grown under MH or HPS lamps or in the greenhouse, showing a correlation with the reduced PAL and TAL activities. Ratios of far red-absorbing phytochrome to total phytochrome were similar for all three lamps, but the data do not yet warrant a conclusion about specific wavelengths missing from the LPS lamps that might have induced PAL and TAL activities in plants under the other lamps.

Triticum/enzymology/growth & development/metabolis↗

Lightning Protection System

A new Lightning Protection System (LPS) was designed and built at Launch Complex 39B (LC-39B), at the Kennedy Space Center (KSC), Florida, in 2009, for NASA’s Space Launch System (SLS) program. A comprehensive lightning monitoring system was additionally designed and the LC-39B lightning instrumentation started incremental deployment early 2011. By March 2011, the LC-39B lightning monitoring system was activated with short outages during construction and renovations of the LC-39B. Since 2011, the LC-39B LPS has been directly struck at least once per year. The earliest and latest in a year that the LPS has been directly struck by lightning has been January 7th and October 1st (both 2017), respectively. During the summer of 2018, the Mobile Launcher 1 (ML-1) lightning monitoring system was deployed and partially active during ML-1 construction/testing. Since 2018, the ML-1 has been parked at the LC-39B for different durations of time for integrated testing. Early August 2019 (6th and 9th ) multiple lightning strikes terminated directly on the LPS at three different locations in addition to a nearby strike within the Pad perimeter and multiple nearby strikes outside the Pad Perimeter, triggering both, the LC-39B and the ML-1 lightning monitoring systems. This has been the first time direct lightning strikes have terminated on the LPS or within the LC-39B perimeter while the ML-1 has been at the LC-39B. This paper summarizes direct and close nearby lightning strikes to LC-39B from 2011 until the summer of 2019.

Angel G Mata↗