186 research outputs found
Development of Liquid Propulsion Systems Testbed at MSFC
As NASA, the Department of Defense and the aerospace industry in general strive to develop capabilities to explore near-Earth, Cis-lunar and deep space, the need to create more cost effective techniques of propulsion system design, manufacturing and test is imperative in the current budget constrained environment. The physics of space exploration have not changed, but the manner in which systems are developed and certified needs to change if there is going to be any hope of designing and building the high performance liquid propulsion systems necessary to deliver crew and cargo to the further reaches of space. To further the objective of developing these systems, the Marshall Space Flight Center is currently in the process of formulating a Liquid Propulsion Systems testbed, which will enable rapid integration of components to be tested and assessed for performance in integrated systems. The manifestation of this testbed is a breadboard engine configuration (BBE) with facility support for consumables and/or other components as needed. The goal of the facility is to test NASA developed elements, but can be used to test articles developed by other government agencies, industry or academia. Joint government/private partnership is likely the approach that will be required to enable efficient propulsion system development. MSFC has recently tested its own additively manufactured liquid hydrogen pump, injector, and valves in a BBE hot firing. It is rapidly building toward testing the pump and a new CH4 injector in the BBE configuration to demonstrate a 22,000 lbf, pump-fed LO2/LCH4 engine for the Mars lander or in-space transportation. The value of having this BBE testbed is that as components are developed they may be easily integrated in the testbed and tested. MSFC is striving to enhance its liquid propulsion system development capability. Rapid design, analysis, build and test will be critical to fielding the next high thrust rocket engine. With the maturity of the BBE testbed, MSFC propulsion engineering will bring forward a national capability that enables growth of both commercial and government interests
A study of vertical imbalance at the reading level
A study of vertical imbalance at the reading leve
The Missionary Hymn
From Greeenland’s icy mountains,From India’s coral strand,Where Afric’s sunny fountainsRoll down their golden sand;From many an ancient river,From many a balmy plain,They call us, to deliverTheir land form error’s chain,They call us to deliverTheir land from error’s chain. What though the spicy breezes,Blow soft on Ceylon’s isle,Though ev’ry prospect pleases,And only man is vile;In vain, with lavish kindness,The gifts of God are strown;The heathen, in his blindness,Bows down to wood and stone.The heathen in his blindness,Bows down to wood and stone.Shall we whose souls are lightedWith wisdom from on highShall we to man benightedThe light of life deny;Salvation! Oh! salvation!The joyful sound proclaim,‘Till each remotest nation,Has learnt Messiah’s name.Till each remote nationHas learnt Messiah’s name. Waft waft ye winds, his story,And you ye waters roll,‘Till like a sea of glory,It spread from pole to pole;‘Till o’er our ransom’d nature,The lamb for sinners slain,Redeemer King, Creator,In bliss return to reign.Redeemer, King , CreatorIn bliss return to reign
Evaluating the Uncertainties in the Electron Temperature and Radial Speed Measurements Using White Light Corona Eclipse Observations
We examine the uncertainties in two plasma parameters from their true values in a simulated asymmetric corona. We use the Corona Heliosphere (CORHEL) and Magnetohydrodynamics Around the Sphere (MAS) models in the Community Coordinated Modeling Center (CCMC) to investigate the differences between an assumed symmetric corona and a more realistic, asymmetric one. We were able to predict the electron temperatures and electron bulk flow speeds to within +/-0.5 MK and +/-100 km s(exp1), respectively, over coronal heights up to 5.0 R from Sun center.We believe that this technique could be incorporated in next-generation white-light coronagraphs to determine these electron plasma parameters in the low solar corona. We have conducted experiments in the past during total solar eclipses to measure the thermal electron temperature and the electron bulk flow speed in the radial direction in the low solar corona. These measurements were made at different altitudes and latitudes in the low solar corona by measuring the shape of the K-coronal spectra between 350 nm and 450 nm and two brightness ratios through filters centered at 385.0 nm/410.0 nm and 398.7 nm/423.3 nm with a bandwidth of is approximately equal to 4 nm. Based on symmetric coronal models used for these measurements, the two measured plasma parameters were expected to represent those values at the points where the lines of sight intersected the plane of the solar limb
Spherical Occulter Coronagraph Cubesat
The present invention relates to a space-based instrument which provides continuous coronal electron temperature and velocity images, for a predetermined period of time, thereby improving the understanding of coronal evolution and how the solar wind and Coronal Mass Ejection transients evolve from the low solar atmosphere through the heliosphere for an entire solar rotation. Specifically, the present invention relates to using a 6U spherical occulter coronagraph CubeSat, and a relative navigational system (RNS) that controls the position of the spacecraft relative to the occulting sphere. The present invention innovatively deploys a free-flying spherical occulter, and after deployment, the actively controlled CubeSat will provide an inertial formation flying with the spherical occulter and Sun
Emerging early actions to bend the curve in Sub-Saharan Africa's nutrition transition
BACKGROUND : Sub-Saharan Africa is the last region to undergo nutrition transition and can still avoid its adverse health outcomes.
OBJECTIVE : The paper explores emerging responses to ―bend the curve‖ in sub-Saharan Africa‘s nutrition transition to steer public health outcomes onto a healthier trajectory.
METHODS : Early responses in three countries at different stages in food system transformation are examined: South Africa -advanced, Ghana –intermediate, and Uganda -early. By comparing these with international experience, actions are proposed to influence nutrition and public health trajectories as Africa‘s food systems undergo rapid structural change.
RESULTS : Arising from rapid urbanization and diet change, major public health problems associated with overweight are taking place, particularly in South Africa and among adult women. However, public health responses are generally tepid in sub-Saharan Africa. Only in South Africa have policy makers instituted extensive actions to combat overweight and associated non-communicable diseases through regulation, education and public health programmes. Elsewhere, in countries in the early and middle stages of transition, public health systems continue to focus their limited resources primarily on under-nutrition. Related pressures on the supply side of Africa‘s food systems are emerging that also need to be addressed.
CONCLUSIONS :Three types of intervention appear most feasible: Maternal and child health programmes to simultaneously address short-term undernutrition problems while at the same time helping to reduce future tendencies towards overweigh; Regulatory and fiscal actions to limit access to unhealthy foods; Modernization of Africa‘s agrifood food system, through job skills training, marketing reforms and food industry entrepreneurship.http://www.elsevier.com /locate/compind2017-06-30hb2016Food Scienc
Global matrix 2.0:Report card grades on the physical activity of children and youth comparing 38 countries
The Active Healthy Kids Global Alliance organized the concurrent preparation of Report Cards on the physical activity of children and youth in 38 countries from 6 continents (representing 60% of the world's population). Nine common indicators were used (Overall Physical Activity, Organized Sport Participation, Active Play, Active Transportation, Sedentary Behavior, Family and Peers, School, Community and the Built Environment, and Government Strategies and Investments), and all Report Cards were generated through a harmonized development process and a standardized grading framework (from A = excellent, to F = failing). The 38 Report Cards were presented at the International Congress on Physical Activity and Public Health in Bangkok, Thailand on November 16, 2016. The consolidated findings are summarized in the form of a Global Matrix demonstrating substantial variation in grades both within and across countries. Countries that lead in certain indicators often lag in others. Average grades for both Overall Physical Activity and Sedentary Behavior around the world are D (low/poor). In contrast, the average grade for indicators related to supports for physical activity was C. Lower-income countries generally had better grades on Overall Physical Activity, Active Transportation, and Sedentary Behaviors compared with higher-income countries, yet worse grades for supports from Family and Peers, Community and the Built Environment, and Government Strategies and Investments. Average grades for all indicators combined were highest (best) in Denmark, Slovenia, and the Netherlands. Many surveillance and research gaps were apparent, especially for the Active Play and Family and Peers indicators. International cooperation and cross-fertilization is encouraged to address existing challenges, understand underlying determinants, conceive innovative solutions, and mitigate the global childhood inactivity crisis. The paradox of higher physical activity and lower sedentary behavior in countries reporting poorer infrastructure, and lower physical activity and higher sedentary behavior in countries reporting better infrastructure, suggests that autonomy to play, travel, or chore requirements and/or fewer attractive sedentary pursuits, rather than infrastructure and structured activities, may facilitate higher levels of physical activity.</p
Investigating variation in replicability
Although replication is a central tenet of science, direct replications are rare in psychology. This research tested variation in the replicability of 13 classic and contemporary effects across 36 independent samples totaling 6,344 participants. In the aggregate, 10 effects replicated consistently. One effect – imagined contact reducing prejudice – showed weak support for replicability. And two effects – flag priming influencing conservatism and currency priming influencing system justification – did not replicate. We compared whether the conditions such as lab versus online or US versus international sample predicted effect magnitudes. By and large they did not. The results of this small sample of effects suggest that replicability is more dependent on the effect itself than on the sample and setting used to investigate the effect
Pathogenic SPTBN1 variants cause an autosomal dominant neurodevelopmental syndrome
SPTBN1 mutations cause a neurodevelopmental syndrome characterized by intellectual disability, language and motor delays, autism, seizures and other features. The variants disrupt beta II-spectrin function and disturb cytoskeletal organization and dynamics. SPTBN1 encodes beta II-spectrin, the ubiquitously expressed beta-spectrin that forms micrometer-scale networks associated with plasma membranes. Mice deficient in neuronal beta II-spectrin have defects in cortical organization, developmental delay and behavioral deficiencies. These phenotypes, while less severe, are observed in haploinsufficient animals, suggesting that individuals carrying heterozygous SPTBN1 variants may also show measurable compromise of neural development and function. Here we identify heterozygous SPTBN1 variants in 29 individuals with developmental, language and motor delays;mild to severe intellectual disability;autistic features;seizures;behavioral and movement abnormalities;hypotonia;and variable dysmorphic facial features. We show that these SPTBN1 variants lead to effects that affect beta II-spectrin stability, disrupt binding to key molecular partners, and disturb cytoskeleton organization and dynamics. Our studies define SPTBN1 variants as the genetic basis of a neurodevelopmental syndrome, expand the set of spectrinopathies affecting the brain and underscore the critical role of beta II-spectrin in the central nervous system
Optics and Quantum Electronics
Contains table of contents for Section 3 and reports on twenty research projects.Charles S. Draper Laboratories Contract DL-H-467138Joint Services Electronics Program Contract DAAL03-92-C-0001Joint Services Electronics Program Grant DAAH04-95-1-0038U.S. Air Force - Office of Scientific Research Contract F49620-91-C-0091MIT Lincoln LaboratoryNational Science Foundation Grant ECS 90-12787Fujitsu LaboratoriesNational Center for Integrated PhotonicsHoneywell Technology CenterU.S. Navy - Office of Naval Research (MFEL) Contract N00014-94-1-0717U.S. Navy - Office of Naval Research (MFEL) Grant N00014-91-J-1956National Institutes of Health Grant NIH-5-R01-GM35459-09U.S. Air Force - Office of Scientific Research Grant F49620-93-1-0301MIT Lincoln Laboratory Contract BX-5098Electric Power Research Institute Contract RP3170-25ENEC
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