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NASA NTRS2000

Aerospace Medicine and Biology: A Continuing Bibliography with Indexes

This supplemental issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes (NASA/SP#2000-7011) lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth#s atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes#subject and author are included after the abstract section.

Source record↗

NASA NTRS2000

Aerospace Medicine and Biology: A Continuing Bibliography With Indexes

Source record↗

NASA NTRS2000

Aerospace Medicine and Biology: A Continuing Bibliography With Indexes

This supplemental issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes (NASA/SP#1999-7011) lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth#s atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes-subject and author are included after the abstract section.

Source record↗

NASA NTRS2000

Aerospace Medicine and Biology: A Continuing Bibliography with Indexes

This supplemental issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes (NASA/SP-1999-7011) lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract.

Source record↗

NASA NTRS2000

Aerospace Medicine and Biology: A Continuing Bibliography With Indexes

This supplemental issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes (NASA/SP-2000-7011) lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes-subject and author are included after the abstract section.

Source record↗

NASA NTRS2000

Aerospace Medicine and Biology: A Continuing Bibliography with Indexes

This supplemental issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes (NASA/SP-2000-7011) lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. Two indexes- subject and author are included after the abstract section.

Source record↗

NASA NTRS2000

Aerospace Medicine and Biology: A Continuing Bibliography With Indexes

This supplemental issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes (NASA/SP#2000-7011) lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion. Each entry in the publication consists of a standard bibliographic citation accompanied, in most cases, by an abstract. The NASA CASI price code table, addresses of organizations, and document availability information are included before the abstract section. Two indexes- subject and author are included after the abstract section.

Source record↗

NASA NTRS1997

Aerospace Medicine and Biology: A Continuing Bibliography With Indexes

This issue of Aerospace Medicine and Biology, A Continuing Bibliography with Indexes NASA SP-7O11 lists reports, articles, and other documents recently announced in the NASA STI Database. In its subject coverage, Aerospace Medicine and Biology concentrates on the biological, physiological, psychological, and environmental effects to which humans are subjected during and following simulated or actual flight in the Earth's atmosphere or in interplanetary space. References describing similar effects on biological organisms of lower order are also included. Such related topics as sanitary problems, pharmacology, toxicology, safety and survival, life support systems, exobiology, and personnel factors receive appropriate attention. Applied research receives the most emphasis, but references to fundamental studies and theoretical principles related to experimental development also qualify for inclusion.

BIBLIOGRAPHIES↗

NASA NTRS2008

Radiative Susceptibility of Cloudy Atmospheres to Droplet Number Perturbations: 1. Theoretical Analysis and Examples from MODIS

Theoretical and satellite-based assessments of the sensitivity of broadband shortwave radiative fluxes in cloudy atmospheres to small perturbations in the cloud droplet number concentration (N) of liquid water clouds under constant water conditions are performed. Two approaches to study this sensitivity are adopted: absolute increases in N, for which the radiative response is referred to as absolute cloud susceptibility, and relative increases in N or relative cloud susceptibility. Estimating the former is more challenging as it requires an assumed value for either cloud liquid water content or geometrical thickness; both susceptibilities require an assumed relationship between the droplet volume and effective radius. Expanding upon previous susceptibility studies, present radiative calculations include the effect of AN perturbations on droplet asymmetry parameter and single-scattering albedo, in addition to extinction. Absolute cloud susceptibility has a strong nonlinear dependence on the droplet effective radius as expected, while relative cloud susceptibility is primarily dependent on optical thickness. Molecular absorption and reflecting surfaces both reduce the relative contribution of the cloud to the top-of-atmosphere (TOA) flux and therefore also reduce the TOA albedo susceptibility. Transmittance susceptibilities are negative with absolute values similar to albedo susceptibility, while atmospheric absorptance susceptibilities are about an order of magnitude smaller than albedo susceptibilities and can be either positive or negative. Observation-based susceptibility calculations are derived from MODIS pixel-level retrievals of liquid water cloud optical thickness, effective radius, and cloud top temperature; two data granule examples are shown. Susceptibility quantifies the aerosol indirect effect sensitivity in a way that can be easily computed from model fields. As such, susceptibilities derived from MODIS observations provide a higher-order test of model cloud properties used for indirect effect studies. MODIS-derived global distributions of cloud susceptibility and radiative forcing calculations are presented in a companion paper.

Platnick, Steven↗

NASA NTRSDate not supplied

A Dominant Arabidopsis Thaliana ACTIN7 Mutant for Studies of Cytoskeletal-Mediated Root Gravity and Spaceflight Stress Responses

A forward genetic screen for Arabidopsis thaliana mutants that exhibited differential sensitivity to the actin-disrupting compound, latrunculin B (LatB), was conducted to uncover new players involved in actin-mediated root gravity responses. This to the isolation of a mutant that exhibited robust primary root growth at 100 nM LatB, which is a concentration that severely inhibits wild-type root elongation. Phenotypic analysis revealed that hypocotyl elongation in the dark and root hair tip growth in the mutant could tolerate LatB concentrations that impaired these processes in wild type. A cross between the mutant and wild type resulted in progeny resistance to LatB, which indicated that the mutant is dominant (hereafter referred to as LBR1 for LatB Resistant1). Filamentous-actin (F-actin) organization in LBR1 primary roots remained intact at 100 nM LatB, while that of wild type exhibited fragmented F-actin. Next generation sequencing revealed that LBR1 had a single nucleotide polymorphism (SNP) in the AT5G09810 gene that changed cytosine to a thiamine at the first exon. AT5G09810 encodes ACTIN7 (ACT7), which is one of three vegetative actin isoforms in A. thaliana. The SNP in the ACT7 gene led to a change in a single amino acid from proline at position 32 to a serine. Transgenic complementation of LBR1 plants with wild-type ACT7 under the control of the ACT7 promoter (pACT7:ACT7) and wild-type plants with LBR1, which contained the proline to serine mutation, also under the ACT7 promoter (pACT7:LBR1) confirmed that LBR1 is ACT7. The pACT7:LBR1 construct was also able to confer LatB resistance to the act7-5 and act2-3 vegetative ACT mutants. Moreover, LBR1 exhibited partial tolerance to salt and low phosphate, and enhanced root skewing on a clinostat, suggesting that site-directed engineering of vegetative ACT presents a strategy for generating stress-tolerant plants for spaceflight applications and studies of actin-mediated gravity responses.

Plant Space Biology↗

NASA NTRSDate not supplied

A Dominant Arabidopsis Thaliana ACTIN7 Mutant for Studies of Cytoskeletal-Mediated Root Gravity and Spaceflight Stress Responses

A forward genetic screen for Arabidopsis thaliana mutants that exhibited differential sensitivity to the actin-disrupting compound, latrunculin B (LatB), was conducted to uncover new players involved in actin-mediated root gravity responses. This led to the isolation of a mutant that exhibited robust primary root growth at 100 nM LatB, which is a concentration that severely inhibits wild-type root elongation. Phenotypic analysis revealed that hypocotyl elongation in the dark and root hair tip growth in the mutant could tolerate LatB concentrations that impaired these processes in wild type. A cross between the mutant and wild type resulted in progeny resistance to LatB, which indicated that the mutant is dominant (hereafter referred to as LBR1 for LatB Resistant1). Filamentous-actin (F-actin) organization in LBR1 primary roots remained intact at 100 nM LatB, while that of wild type exhibited fragmented F-actin. Next generation sequencing revealed that LBR1 had a single nucleotide polymorphism (SNP) in the AT5G09810 gene that changed cytosine to a thiamine at the first exon. AT5G09810 encodes ACTIN7 (ACT7), which is one of three vegetative actin isoforms in A. thaliana. The SNP in the ACT7 gene led to a change in a single amino acid from proline at position 32 to a serine. Transgenic complementation of LBR1 plants with wild-type ACT7 under the control of the ACT7 promoter (pACT7:ACT7) and wild-type plants with LBR1, which contained the proline to serine mutation, also under the ACT7 promoter (pACT7:LBR1) confirmed that LBR1 is ACT7. The pACT7:LBR1 construct was also able to confer LatB resistance to the act7-5 and act2-3 vegetative ACT mutants. Moreover, LBR1 exhibited partial tolerance to salt and low phosphate, and enhanced root skewing on a clinostat, suggesting that site-directed engineering of vegetative ACT presents a strategy for generating stress-tolerant plants for spaceflight applications and studies of actin-mediated gravity responses.

Plant Space Biology↗

NASA NTRS2023

On More than Two Decades of Celestial Reference Frame VLBI Observations in the Deep South: IVS-CRDS (1995 - 2021)

The International VLBI Service for Geodesy & Astrometry (IVS) regularly provides high-quality data to produce Earth Orientation Parameters (EOP), and for the maintenance and realization of the International Terrestrial and Celestial Reference Frames, ITRF and ICRF. The first iteration of the celestial reference frame (CRF) at radio wavelengths, the ICRF1, was adopted by the International Astronomical Union (IAU) in 1997 to replace the FK5 optical frame. Soon after, the IVS began official operations and in 2009 there was a significant increase in data sufficient to warrant a second iteration of the CRF, ICRF2. The most recent ICRF3, was adopted by the IAU in 2018. However, due to the geographic distribution of observing stations being concentrated in the Northern hemisphere, CRFs are generally weaker in the South due to there being fewer Southern Hemisphere observations. To increase the Southern Hemisphere observations, and the density, precision of the sources, a series of deep South observing sessions was initiated in 1995. This initiative in 2004 became the IVS Celestial Reference Frame Deep South (IVS-CRDS) observing program. This paper covers the evolution of the CRDS observing program for the period 1995 to 2021, details the data products and results, and concludes with a summary of upcoming improvements to this ongoing project.

VLBI↗

DOE OSTI2026

Two-stage formation-energy correction (NbZr, TaZr, VZr)

This bundle contains the scripts, the raw and corrected per-structure data, and the manuscript plots for the NbZr / TaZr / VZr BCC binary formation energies and the associated RMSDs. Why a two-stage correction is necessary: The "raw" formation energy of every relaxed VASP configuration is computed in the usual way, FE_raw(c) = E_alloy(c) - sum_i x_i * E_pure_i , where E_pure_i are the per-atom total energies of the pure-element reference structures (Nb, Ta, V, Zr in the same BCC supercell, with identical INCAR / KPOINTS / PAW choices). With perfectly consistent reference runs the raw FE should vanish at the two pure-element endpoints (x = 0 and x = 1) by construction. In practice this does not hold for two reasons that are present in our dataset: 1. Reference-energy inconsistency (composition-dependent bias). Even with identical input parameters, the pure-element runs (stored in `corrected_DFT_pure_element_runs/`) differ slightly from the values that would be implied by the alloy runs at near-pure compositions (a few meV/atom). This bias is approximately linear in concentration, because the residual error in E_pure_Nb (or E_pure_Ta / E_pure_V) propagates into FE_raw(c) as (1 - x) * dE_pure_1, and the corresponding error in E_pure_Zr propagates as x * dE_pure_2. Left uncorrected, this produces a non-physical "tilt" of FE_raw(x) and shifts the entire FE-vs-x cloud away from zero at the endpoints. 2. Endpoint anchoring against the audited true endpoints. The strict endpoint values (FE_x0_meVatom, FE_x1_meVatom in `corrected_fe_strict_endpoints_20260518/strict_endpoint_check_20260518.csv`) were re-derived from an independent cross-check of the pure-element runs. After stage 1 removes the linear bias, the near-pure compositions in the alloy dataset still extrapolate to values that differ slightly from these audited endpoints — because stage 1 is fit from a few near-end alloy bins, not from the audited pure-element references themselves. The README.txt file discusses how these issues are addressed by the two-stage correction, and describes folder layout, pipeline summary, and how to re-run.

36 MATERIALS SCIENCE↗

DOE OSTI2021

Thermophysical Properties of Mixtures of Thorium and Uranium Nitride

Abstract The miscibility, lattice parameter, and thermophysical properties of (Th 0.2 U 0.8 )N and (Th 0.5 U 0.5 )N have been investigated. It is shown that additions of thorium nitride (ThN) to uranium nitride (UN) increases the thermophysical performance of the mixed nitride fuel form in comparison to reference UN. In the more dilute limit, additions of ThN serve as a burnable neutronic poison and reduces the change in k eff over the lifecycle of the fuel. At higher concentrations, additions of ThN serve as a significant fertile source of 233 U. Where appropriate, comparisons to previous work on UN + PuN mixtures are made, as this is a comparable fuel form for potential fast reactor concepts, and a suitable point of contrast in the possible design space afforded by mixed (Th x U 1 − x )N fuel forms. The data from this work are the input parameters for finite element modeling of the temperature distribution in a compact reactor. The results of modeling and simulation of this core design are shown for the case of steady-state operation and during double, adjacent heat pipe failure.

Parker, S. S. (ORCID:000000018597440X)↗

DOE OSTI2025

Adsorptive denitrogenation of model aviation fuel using mesoporous silica in a packed bed adsorption system

This study aims to understand the effects of system process parameters such as flow rate, adsorbent particle size, and use of recycled adsorbent on denitrogenation performance of a model fuel using mesoporous silica gel. The goal is to reduce the nitrogen content of the model fuel from 1500 parts per million to single-digit ppm to meet ASTM specifications for drop-in fuels. This work was done with the intent of applying adsorptive denitrogenation to sustainable aviation fuel (SAF) product fractions produced via hydrothermal liquefaction (HTL). The adsorption performance of the silica is evaluated via packed column breakthrough data, with data generated from collecting from the column outlet and quantifying nitrogen content via gas chromatography. Select experiments use a significantly larger (2.5x column diameter and length) column to demonstrate linear scalability of the process. Thermogravimetric analysis data is collected to evaluate the effects of thermal calcination as a sorbent regeneration method. Effects of a more complex feed are also investigated using a known reference fuel with additional added nitrogen containing compounds. The results presented in this work successfully demonstrate up to 99.8 % removal of NCCs from a model fuel fraction at an original NCC concentration of approximately 1500 ppm to single-digit parts per million after treatment. We also examine calcination of sorbent materials to remove the adsorbed species to enable sorbent reuse and minimize waste generation and show that the calcined material can be reused up to 5 cycles with reduced adsorption capacity. Overall, this work indicates that adsorptive denitrogenation using silica gel is a viable solution to enable the integration of HTL-derived aviation fuels into existing fuel infrastructure.

Adsorption techniques↗

DOE OSTI2024

Multilayer Silicon Carbide Composite Material Technology for High-Temperature Concentrated Solar-Thermal Power Components

In 2012, the U.S Department of Energy defined aggressive targets to achieve lower component costs and higher system efficiencies for concentrated solar-thermal power (CSP), and this, in turn, has led to the exploration of technology options that can operate at higher temperatures [1]. These next-generation CSP options, referred to as Generation 3 (a.k.a. Gen3), are targeting temperatures at or above 700 °C for the energy being delivered to the power cycle, and the more challenging plant conditions have necessitated a review and selection of alternative receiver heat transfer fluids as well as a search for materials that can meet the associated high-temperature component requirements. Nickel-based alloys are currently being considered, but these generally experience a significant drop in strength at temperatures > 775 °C [2] and may not be able to achieve corrosion and other lifetime requirements. Furthermore, these alloys are expensive, frequently have cost and schedule volatility, and offer little potential for lower cost at high production volumes. As an alternative, Ceramic Tubular Products, LLC (CTP) has developed a multilayer silicon carbide composite that can complement or replace alloys currently being considered for these Gen3 CSP applications.

14 SOLAR ENERGY↗

NASA NTRS1984

Arctic atmosphere - Ice interaction studies using Nimbus-7 SMMR

The use of data from the Scanning Multichannel Microwave Radiometer (SMMR) on board Nimbus 7 for studying ice-atmosphere interactions is discussed with reference to two case studies, one for the Greenland Sea and the other for the Sea of Okhotsk, for April/May 1979. By using SMMR data, rapid changes in ice extent and concentration have been observed in association with changes in synoptic atmospheric circulation. Case studies and analyses of sample data indicate that ice concentration estimates may be accurate to within 10 percent.

Anderson, M. R.↗

NASA NTRS1923

Bending moments, envelope, and cable stresses in non-rigid airships

This report describes the theory of calculating the principal stresses in the envelope of a nonrigid airship used by the Bureau of Aeronautics, United States Navy. The principal stresses are due to the gas pressure and the unequal distribution of weight and buoyancy, and the concentrated loads from the car suspension cables. The second part of the report deals with the variations of tensions in the car suspension cables of any type of airship, with special reference to the rigid type, due to the propeller thrust or the inclination of the airship longitudinally.

Burgess, C P↗