Search NASA⌕ Search

SEARCH · Search NASA

Results for “Group 7”

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.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 325 records · Page 18
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Fe4As3O23 by Materials Project

(Fe4As3O16)2(O2)7 crystallizes in the cubic P-43m space group. The structure is three-dimensional and consists of seven water molecules and one Fe4As3O16 framework. In the Fe4As3O16 framework, Fe is bonded to six O atoms to form FeO6 octahedra that share corners with three equivalent AsO4 tetrahedra and edges with three equivalent FeO6 octahedra. There is three shorter (1.93 Å) and three longer (2.00 Å) Fe–O bond length. As is bonded to four equivalent O atoms to form AsO4 tetrahedra that share corners with four equivalent FeO6 octahedra. The corner-sharing octahedral tilt angles are 54°. All As–O bond lengths are 1.72 Å. There are two inequivalent O sites. In the first O site, O is bonded in a distorted trigonal non-coplanar geometry to three equivalent Fe atoms. In the second O site, O is bonded in a bent 120 degrees geometry to one Fe and one As atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ge7O23 by Materials Project

(Ge7O16)2(O2)7 crystallizes in the cubic P-43m space group. The structure is three-dimensional and consists of seven water molecules and one Ge7O16 framework. In the Ge7O16 framework, there are two inequivalent Ge sites. In the first Ge site, Ge is bonded to six O atoms to form GeO6 octahedra that share corners with three equivalent GeO4 tetrahedra and edges with three equivalent GeO6 octahedra. There is three shorter (1.83 Å) and three longer (2.03 Å) Ge–O bond length. In the second Ge site, Ge is bonded to four equivalent O atoms to form corner-sharing GeO4 tetrahedra. The corner-sharing octahedral tilt angles are 56°. All Ge–O bond lengths are 1.76 Å. There are two inequivalent O sites. In the first O site, O is bonded in a bent 120 degrees geometry to two Ge atoms. In the second O site, O is bonded in a trigonal non-coplanar geometry to three equivalent Ge atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Al4As3O23 by Materials Project

(Al4As3O16)2(O2)7 crystallizes in the cubic P-43m space group. The structure is three-dimensional and consists of seven water molecules and one Al4As3O16 framework. In the Al4As3O16 framework, Al is bonded to six O atoms to form AlO6 octahedra that share corners with three equivalent AsO4 tetrahedra and edges with three equivalent AlO6 octahedra. There is three shorter (1.85 Å) and three longer (1.96 Å) Al–O bond length. As is bonded to four equivalent O atoms to form AsO4 tetrahedra that share corners with four equivalent AlO6 octahedra. The corner-sharing octahedral tilt angles are 56°. All As–O bond lengths are 1.71 Å. There are two inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to three equivalent Al atoms. In the second O site, O is bonded in a bent 120 degrees geometry to one Al and one As atom.

36 MATERIALS SCIENCE↗
NASA NTRS1971

Absolute cross section for the production of O/super 5 S super 0/ by electron impact dissociation of O2.

Estimation of the aeronomically important cross section for the production of O(super 5 S super 0) by electron impact dissociation of O2 on the basis of recently published work of several groups. The cross section reaches a maximum value of 7 x 10 to the minus 18th sq cm plus or minus 50% at about 100 eV. The assumptions made in arriving at this cross section suggest several experiments which might be performed to further refine this estimate.

Wells, W. C.↗
NASA NTRS1973

Heat flow and convection demonstration (Apollo 14)

Apollo 14 Astronaut Stuart A. Roosa conducted a group of experiments during the lunar flyback on February 7, 1971, to obtain information on heat flow and convection in gases and liquids in an environment of less than 0.000001 g. Flow observations and thermal data have shown that: (1) as expected, there are convective motions caused by surface tension gradients in a plane liquid layer with a free upper surface; (2) heat flow in enclosed liquids and gases occurs mainly by diffusive heat conduction; and (3) some convective processes, whose characteristics are not fully known, add to the heat transfer. The raw data are presented, and the analysis approach is given.

Bannister, T. C.↗
NASA NTRS2003

Host resistance of CD18 knockout mice against systemic infection with Listeria monocytogenes

Mice with targeted mutations of CD18, the common beta2 subunit of CD11/CD18 integrins, have leukocytosis, impaired transendothelial neutrophil emigration, and reduced host defense to Streptococcus pneumoniae, a gram-positive extracellular bacterium. Previous studies using blocking monoclonal antibodies suggested roles for CD18 and CD11b in hepatic neutrophil recruitment and host innate response to Listeria monocytogenes, a gram-positive intracellular bacterium. We induced systemic listeriosis in CD18 knockout (CD18-ko) and wild-type (WT) mice by tail vein injection with Listeria. By 14 days postinjection (dpi), 8 of 10 WT mice died, compared with 2 of 10 CD18-ko mice (P < 0.01). Quantitative organ culture showed that numbers of Listeria organisms in livers and spleens were similar in both groups at 20 min postinfection. By 3, 5, and 7 dpi, however, numbers of Listeria organisms were significantly lower in livers and spleens of CD18-ko mice than in WT mice. Histopathology showed that following Listeria infection, CD18-ko mice had milder inflammatory and necrotizing lesions in both spleens and livers than did WT mice. Cytokine assays indicated that baseline interleukin-1beta and granulocyte colony-stimulating factor (G-CSF) levels were higher in CD18-ko mice than in WT mice and that CD18-ko splenocytes produced higher levels of interleukin-1beta and G-CSF than WT splenocytes under the same amount of Listeria stimulation. These findings show that CD18 is not an absolute requirement for antilisterial innate immunity or hepatic neutrophil recruitment. We propose that the absence of CD18 in the mice results in the priming of innate immunity, as evidenced by elevated cytokine expression, and neutrophilic leukocytosis, which augments antilisterial defense.

Non-NASA Center↗
NASA NTRS1995

Person-to-person transfer of Candida albicans in the spacecraft environment

We assessed the exchange of Candida albicans among crew members during 10 Space Shuttle missions. Throat, nasal, urine and faecal specimens were collected from 61 crew members twice before and once after space flights ranging from 7 to 10 days in duration; crews consisted of groups of five, six or seven men and women. Candida albicans was isolated at least once from 20 of the 61 subjects (33%). Candida strains were identified by restriction-fragment length polymorphism (RFLP) after digestion by the endonucleases EcoRI and HinfI; further discrimination was gained by Southern blot hybridization with the C. albicans repeat fragment 27A. Eighteen of the 20 Candida-positive crew members carried different strains of C. albicans in the specimens collected. Possible transfer of C. albicans between members of the same crew was demonstrated only once in the 10 missions studied. We conclude that the transfer of C. albicans among crew members during Space Shuttle flights is less frequent than had been predicted from earlier reports.

Flight Experiment↗
NASA NTRS2007

Rb-Sr and Sm-Nd Isotopic Studies of Martian Depleted Shergottes SaU 094/005

Sayh al Uhaymir (SaU) 094 and SaU 005 are olivine-phyric shergottites from the Oman desert and are considered as pairs. [e.g., 1]. They are very similar to the Libyan desert shergottite Dar al Gani (DaG) 476 in petrology, chemistry and ejection age [2-6]. This group of shergottites, also recognized as depleted shergottites [e.g. 7] has been strongly shocked and contains very low abundances of light rare earth elements (REE). In addition, terrestrial contaminants are commonly present in meteorites found in desert environments. Age-dating these samples is very challenging, but lower calcite contents in the SaU meteorites suggest that they have been subjected to less severe desert weathering than their DaG counterparts [3-4]. In this report, we present Rb-Sr and Sm-Nd isotopic results for SaU 094 and SaU 005, discuss the correlation of their ages with those of other similar shergottites, and discuss their petrogenesis.

Shih, C.-Y.↗
NASA NTRS2011

Contribution of Satellite Gravimetry to Understanding Seismic Source Processes of the 2011 Tohoku-Oki Earthquake

The 2011 great Tohoku-Oki earthquake, apart from shaking the ground, perturbed the motions of satellites orbiting some hundreds km away above the ground, such as GRACE, due to coseismic change in the gravity field. Significant changes in inter-satellite distance were observed after the earthquake. These unconventional satellite measurements were inverted to examine the earthquake source processes from a radically different perspective that complements the analyses of seismic and geodetic ground recordings. We found the average slip located up-dip of the hypocenter but within the lower crust, as characterized by a limited range of bulk and shear moduli. The GRACE data constrained a group of earthquake source parameters that yield increasing dip (7-16 degrees plus or minus 2 degrees) and, simultaneously, decreasing moment magnitude (9.17-9.02 plus or minus 0.04) with increasing source depth (15-24 kilometers). The GRACE solution includes the cumulative moment released over a month and demonstrates a unique view of the long-wavelength gravimetric response to all mass redistribution processes associated with the dynamic rupture and short-term postseismic mechanisms to improve our understanding of the physics of megathrusts.

Han, Shin-Chan↗
NASA NTRS2013

Evidence for Extended Aqueous Alteration in CR Carbonaceous Chondrites

We are currently studying the chemical interrelationships between the main rockforming components of carbonaceous chondrites (hereafter CC), e.g. silicate chondrules, refractory inclusions and metal grains, and the surrounding meteorite matrices. It is thought that the fine-grained materials that form CC matrices are representing samples of relatively unprocessed protoplanetary disk materials [1-3]. In fact, modern non-destructive analytical techniques have shown that CC matrices host a large diversity of stellar grains from many distinguishable stellar sources [4]. Aqueous alteration has played a role in homogeneizing the isotopic content that allows the identification of presolar grains [5]. On the other hand, detailed analytical techniques have found that the aqueously-altered CR, CM and CI chondrite groups contain matrices in which the organic matter has experienced significant processing concomitant to the formation of clays and other minerals. In this sense, clays have been found to be directly associated with complex organics [6, 7]. CR chondrites are particularly relevant in this context as this chondrite group contains abundant metal grains in the interstitial matrix, and inside glassy silicate chondrules. It is important because CR are known for exhibiting a large complexity of organic compounds [8-10], and only metallic Fe is considered essential in Fischer-Tropsch catalysis of organics [11-13]. Therefore, CR chondrites can be considered primitive materials capable to provide clues on the role played by aqueous alteration in the chemical evolution of their parent asteroids.

Trigo-Rodriquez, J. M.↗
NASA NTRS2014

9-Ft By 7-Ft Supersonic Wind Tunnel Nozzle Improvement Study

Engineers at the Unitary Plan Wind Tunnel at NASA Ames Research Center have recently embarked on a project focused on improving flow quality and tunnel capabilities in the 9-ft by 7-ft supersonic wind tunnel. Collaborating with Jacobs Tech Group, the project has explored potential improvements to the nozzle design using computational fluid dynamics. Preliminary predictions suggest changes to the nozzle design could significantly improve flow quality at the lower operating range (M1.5-1.8), however potential improvements in the upper operating range have yet to be realized.

Wind Tunnel Testing↗
DOE OSTI2020

Materials Data on Ba5(Bi2O3)7 by Materials Project

Ba5Bi10O17(BiO)4 crystallizes in the triclinic P1 space group. The structure is two-dimensional and consists of one Ba5Bi10O17 sheet oriented in the (0, 0, 1) direction and two BiO sheets oriented in the (0, 0, 1) direction. In the Ba5Bi10O17 sheet, there are five inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a 9-coordinate geometry to nine O2- atoms. There are a spread of Ba–O bond distances ranging from 2.73–3.12 Å. In the second Ba2+ site, Ba2+ is bonded to six O2- atoms to form distorted BaO6 octahedra that share corners with four equivalent BaO6 octahedra, edges with four equivalent BaO6 octahedra, and edges with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 24–25°. There are a spread of Ba–O bond distances ranging from 2.59–2.98 Å. In the third Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.64–3.13 Å. In the fourth Ba2+ site, Ba2+ is bonded to five O2- atoms to form a mixture of distorted edge and corner-sharing BaO5 trigonal bipyramids. There are a spread of Ba–O bond distances ranging from 2.65–2.83 Å. In the fifth Ba2+ site, Ba2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Ba–O bond distances ranging from 2.61–2.98 Å. There are ten inequivalent Bi+2.29+ sites. In the first Bi+2.29+ site, Bi+2.29+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Bi–O bond distances ranging from 2.05–2.84 Å. In the second Bi+2.29+ site, Bi+2.29+ is bonded to six O2- atoms to form distorted BiO6 octahedra that share corners with four equivalent BiO6 octahedra, edges with four equivalent BaO6 octahedra, and edges with four equivalent BiO6 octahedra. The corner-sharing octahedra tilt angles range from 2–15°. There are a spread of Bi–O bond distances ranging from 2.28–2.98 Å. In the third Bi+2.29+ site, Bi+2.29+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.33–2.97 Å. In the fourth Bi+2.29+ site, Bi+2.29+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Bi–O bond distances ranging from 2.14–2.61 Å. In the fifth Bi+2.29+ site, Bi+2.29+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. There are a spread of Bi–O bond distances ranging from 2.52–2.94 Å. In the sixth Bi+2.29+ site, Bi+2.29+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. There are a spread of Bi–O bond distances ranging from 2.49–2.76 Å. In the seventh Bi+2.29+ site, Bi+2.29+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.20–2.96 Å. In the eighth Bi+2.29+ site, Bi+2.29+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Bi–O bond distances ranging from 2.16–2.59 Å. In the ninth Bi+2.29+ site, Bi+2.29+ is bonded to six O2- atoms to form a mixture of distorted edge and corner-sharing BiO6 octahedra. The corner-sharing octahedra tilt angles range from 2–15°. There are a spread of Bi–O bond distances ranging from 2.30–2.98 Å. In the tenth Bi+2.29+ site, Bi+2.29+ is bonded in a 4-coordinate geometry to five O2- atoms. There are a spread of Bi–O bond distances ranging from 2.18–2.98 Å. There are seventeen inequivalent O2- sites. In the first O2- site, O2- is bonded in a 5-coordinate geometry to four equivalent Ba2+ and one O2- atom. The O–O bond length is 1.50 Å. In the second O2- site, O2- is bonded in a 1-coordinate geometry to one Ba2+, one Bi+2.29+, and one O2- atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to four equivalent Ba2+ and one Bi+2.29+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+ and three equivalent Bi+2.29+ atoms. In the fifth O2- site, O2- is bonded to four equivalent Ba2+ and one Bi+2.29+ atom to form a mixture of distorted edge and corner-sharing OBa4Bi trigonal bipyramids. In the sixth O2- site, O2- is bonded in a 6-coordinate geometry to two Ba2+ and four equivalent Bi+2.29+ atoms. In the seventh O2- site, O2- is bonded to four equivalent Ba2+ and one Bi+2.29+ atom to form a mixture of distorted edge and corner-sharing OBa4Bi trigonal bipyramids. In the eighth O2- site, O2- is bonded in a 5-coordinate geometry to one Ba2+ and four equivalent Bi+2.29+ atoms. In the ninth O2- site, O2- is bonded in a 4-coordinate geometry to four Bi+2.29+ atoms. In the tenth O2- site, O2- is bonded in a 4-coordinate geometry to four Bi+2.29+ atoms. In the eleventh O2- site, O2- is bonded in a 4-coordinate geometry to four Bi+2.29+ atoms. In the twelfth O2- site, O2- is bonded in a 4-coordinate geometry to five Bi+2.29+ atoms. In the thirteenth O2- site, O2- is bonded in a 4-coordinate geometry to one Ba2+ and three equivalent Bi+2.29+ atoms. In the fourteenth O2- site, O2- is bonded to five Ba2+ atoms to form a mixture of distorted edge and corner-sharing OBa5 trigonal bipyramids. In the fifteenth O2- site, O2- is bonded to four equivalent Ba2+ and one Bi+2.29+ atom to form distorted OBa4Bi trigonal bipyramids that share a cornercorner with one OBi4 tetrahedra, corners with eight OBa5 trigonal bipyramids, and edges with four equivalent OBa4Bi trigonal bipyramids. In the sixteenth O2- site, O2- is bonded in a 6-coordinate geometry to one Ba2+ and five Bi+2.29+ atoms. In the seventeenth O2- site, O2- is bonded to four Bi+2.29+ atoms to form distorted OBi4 tetrahedra that share corners with six equivalent OBi4 tetrahedra and a cornercorner with one OBa4Bi trigonal bipyramid. In each BiO sheet, there are two inequivalent Bi+2.29+ sites. In the first Bi+2.29+ site, Bi+2.29+ is bonded in a 2-coordinate geometry to three equivalent O2- atoms. There are a spread of Bi–O bond distances ranging from 2.35–2.98 Å. In the second Bi+2.29+ site, Bi+2.29+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Bi–O bond distances ranging from 2.12–2.85 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to four Bi+2.29+ atoms. In the second O2- site, O2- is bonded in a 2-coordinate geometry to three equivalent Bi+2.29+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Swampland cobordism conjecture and non-Abelian duality groups

We study the cobordism conjecture of McNamara and Vafa which asserts that the bordism group of quantum gravity is trivial. In the context of type IIB string theory compactified on a circle, this predicts the presence of D7-branes. On the other hand, the non-Abelian structure of the IIB duality group SL (2, Z) implies the existence of additional [p, q] 7-branes. We find that this additional information is instead captured by the space of closed paths on the moduli space of elliptic curves parameterizing distinct values of the type IIB axio-dilaton. This description allows to recover the full structure of non-Abelian braid statistics for 7-branes. Combining the cobordism conjecture with an earlier Swampland conjecture by Ooguri and Vafa, we argue that only certain congruence subgroups $\Gamma\subset$ SL(2, Z) specifying genus zero modular curves can appear in 8D F-theory vacua. This leads to a successful prediction for the allowed Mordell–Weil torsion groups for 8D F-theory vacua.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2023

Crystal structure of meglumine diatrizoate, (C 7 H 18 NO 5 )(C 11 H 8 I 3 N 2 O 4 )

The crystal structure of meglumine diatrizoate has been solved and refined using synchrotron X-ray powder diffraction data and optimized using density functional theory techniques. Meglumine diatrizoate crystallizes in space group P2 1 (#4) with a = 10.74697(4), b = 6.49364(2), c = 18.52774(7) Å, β = 90.2263(3), V = 1292.985(5) Å 3 , and Z = 2. Two different crystal structures, which yielded essentially identical refinement residuals and positions of the non-H atoms, were obtained. The differences were in the H atom positions and the hydrogen bonding. One structure was 123.0 kJ/mol/cell lower in energy than the other and was adopted for the final description. The crystal structure consists of alternating double layers of cations and anions along the c-axis. The hydrogen bonds link the cations and anions into a three-dimensional framework. Each of the hydrogen atoms on the ammonium nitrogen of the cation acts as a donor in a strong N–H∙∙∙O hydrogen bond. One of these is to a hydroxyl group of another cation, and the other is to the carboxylate group of the anion. Each of the amide nitrogen atoms of the anion forms a strong N–H∙∙∙O intermolecular hydrogen bond, one to a carbonyl and the other to a carboxylate group. The powder pattern has been submitted to ICDD for inclusion in the Powder Diffraction File™ (PDF®).

36 MATERIALS SCIENCE↗
NASA NTRS1986

Uniform engine testing program phase 7: NASA Lewis Research Center second entry

The propulsion and Energetics Panel, Working Group 15, of the Advisory Group for Aerospace Research and Development (AGARD) is sponsoring a Uniform Engine Testing Program (UETP). In this program, two jet engines were tested under identical conditions in certain NATO altitude and ground-level facilities as a means of correlating these facilities. With this second entry, NASA documented engine deterioration that may have occurred since inception of the UETP. Additionally, NASA investigated anomalies discovered during review of data from the five facilities which had participated in the program between the two NASA entries.

Biesiadny, T. J.↗
NASA NTRS2004

Status of the Landsat Data Continuity Mission

Efforts to begin implementing a successor mission to Landsat 7, called the Landsat Data Continuity Mission (LDCM), suffered a set back in 2003. NASA and the Department of Interior (DOI)/U.S. Geological Survey (USGS) currently manage the Landsat Program as an interagency partnership. The two agencies had planned to purchase data meeting LDCM specifications from a privately owned and commercially operated satellite system beginning in March, 2007. This approach represented a departure from the traditional procurement of a government owned and operated satellite system. NASA, however, cancelled a Request-for-Proposals (RFP) for providing the required data after an evaluation of proposals received from private industry. NASA concluded that the proposals failed to meet a key objective and expectation of the RFP, namely, to form a fair and equitable partnership between the Government and private industry. Alternative strategies for implementing an LDCM are now under consideration. The Executive Office of the President formed an interagency working group on the LDCM following the RFP cancellation. The working group is considering other options for implementing a successor system to Landsat 7 consistent with the Land Remote Sensing Policy Act of 1992 (Public Law 102-555). This Act lists four management options for consideration: 1) private sector funding and management; 2) an international consortium; 3) funding and management by the U.S. Government; and 4) a cooperative effort between the US. Government and the private sector. The working group is currently attempting to minimize the risk of a Landsat data gap through development of a strategy that leads to a Landsat 7 successor mission. The selected strategy and the status of the mission will be presented at the Symposium.

Irons, James R.↗
NASA NTRS2013

Preparation and Single-Crystal X-Ray Structures of Four Related Mixed-Ligand 4-Methylpyridine Indium Halide Complexes

We describe the structures of four related indium complexes obtained during synthesis of solid-state materials precursors. Indium adducts of halides and 4-methylpyridine, InX3(pic)3 (X = Cl, Br; pic = 4-methylpyridine) consist of octahedral molecules with meridional (mer) geometry. Crystals of mer-InCl3(pic)3 (1) are triclinic, space group P1(bar) (No. 2), with a = 9.3240(3), b = 13.9580(6), c = 16.7268 (7) A, alpha = 84.323(2), beta = 80.938(2), gamma = 78.274(3)Z = 4, R = 0.035 for 8820 unique reflections. Crystals of mer-InBr3(pic)3 (2) are monoclinic, space group P21/n (No. 14), with a = 15.010(2), b = 19.938(2), c = 16.593(3), beta = 116.44(1)Z = 8, R = 0.053 for 4174 unique reflections. The synthesis and structures of related compounds with phenylsulfide (chloride) (3) and a dimeric complex with bridging hydroxide (bromide) (4) coordination is also described. Crystals of trans-In(SC6H5)Cl2(pic)3 (3) are monoclinic, space group P21/n (No. 14), with a = 9.5265(2), b = 17.8729(6), c = 13.8296(4), beta = 99.7640(15)Z = 4, R = 0.048 for 5511 unique reflections. Crystals of [In(mu-OH)Br2(pic)22 (4) are tetragonal, space group = I41cd (No. 110) with a = 19.8560(4), b = 19.8560(4), c = 25.9528(6), Z = 8, R = 0.039 for 5982 unique reflections.

Hepp, Aloysius F.↗
NASA NTRS2000

Autogenic-feedback training exercise is superior to promethazine for control of motion sickness symptoms

Motion sickness symptoms affect approximately 50% of the crew during space travel and are commonly treated with intramuscular injections of promethazine. The purpose of this paper is to compare the effectiveness of three treatments for motion sickness: intramuscular injections (i.m.) of promethazine, a physiological training method (autogenic-feedback training exercise [AFTE]), and a no-treatment control. An earlier study tested the effects of promethazine on cognitive and psychomotor performance and motion sickness tolerance in a rotating chair. For the present paper, motion sickness tolerance, symptom reports, and physiological responses of these subjects were compared to matched subjects selected from an existing database who received either AFTE or no treatment. Three groups of 11 men, between the ages of 33 and 40 years, were matched on the number of rotations tolerated during their initial rotating-chair motion sickness test. The motion sickness test procedures and the 7-day interval between tests were the same for all subjects. The drug group was tested under four treatment conditions: baseline (no injections), a 25 mg dose of promethazine, a 50 mg dose of promethazine, and a placebo of sterile saline. AFTE subjects were given four 30-minute AFTE sessions before their second, third, and fourth motion sickness tests (6 hours total). The no-treatment control subjects were only given the four rotating-chair tests. Motion sickness tolerance was significantly increased after 4 hours of AFTE when compared to either 25 mg (p < 0.00003) or 50 mg (p < 0.00001) of promethazine. The control and promethazine groups did not differ. AFTE subjects reported fewer or no symptoms at higher rotational velocities than subjects in the control or promethazine groups. The primary physiological effect of promethazine was an inhibition of skin conductance level. The AFTE group showed significantly less heart rate and skin conductance variability during motion sickness tests administered after training.

Clinical Trial↗