A review and evaluation of the Langley Research Center's Scientific and Technical Information Program. Results of phase 4: Knowledge and attitudes survey, academic and industrial personnel

Feedback from engineers and scientists in the academic and industrial community provided an assessment of the usage and perceived quality of NASA Langley generated STI and the familiarity and usage of selected NASA publications and services and identified ways to increase the accessibility of Langley STI. The questionnaire utilized both open and closed ended questions and was pretested for finalization. The questions were organized around the seven objectives for Phase IV. From a contact list of nearly 1,200 active industrial and academic researchers, approximately 600 addresses were verified. The 497 persons who agreed to participate were mailed questionnaires. The 381 completed questionnaires received by the cutoff date were analyzed. Based on the survey findings, recommendations were made for increasing the familiarity with and use of NASA and Langley STI and selected NASA publications and services. In addition, recommendations were made for increasing the accessibility of Langley STI

Future directions in aeropropulsion technology

Future directions in aeropropulsion technology that have been identified in a series of studies recently sponsored by the U.S. Government are discussed. Advanced vehicle concepts that could become possible by the turn of the century are presented along with some of their projected capabilities. Key building-block propulsion technologies that will contribute to making these vehicle concepts a reality are discussed along with projections of their status by the year 2000. Some pertinent highlights of the NASA aeropropulsion program are included in the discussion

Exploring the Structure of Distant Galaxies with Adaptive Optics on the Keck-II Telescope

We report on the first observation of cosmologically distant field galaxies with an high order Adaptive Optics (AO) system on an 8-10 meter class telescope. Two galaxies were observed at 1.6 microns at an angular resolution as high as 50 milliarcsec using the AO system on the Keck-II telescope. Radial profiles of both objects are consistent with those of local spiral galaxies and are decomposed into a classic exponential disk and a central bulge. A star-forming cluster or companion galaxy as well as a compact core are detected in one of the galaxies at a redshift of 0.37+/-0.05. We discuss possible explanations for the core including a small bulge, a nuclear starburst, or an active nucleus. The same galaxy shows a peak disk surface brightness that is brighter than local disks of comparable size. These observations demonstrate the power of AO to reveal details of the morphology of distant faint galaxies and to explore galaxy evolution.Comment: 5 pages, Latex, 3 figures. Accepted for publication in P.A.S.

New Technology In Turbine Aerodynamics

PaperPg. 105-118.This paper presents a cursory review of some of the recent work that has been done in turbine aerodynamic research at NASA-Lewis Research Center. Topics discussed include the aerodynamic effect of turbine coolant, high work-factor (ratio of stage work to square of blade speed) turbines, and computer methods for turbine design and performance prediction. An extensive bibliography is included. Experimental cooled-turbine aerodynamics programs using two-dimensional cascades, full annular cascades, and cold rotating turbine stage tests are discussed with some typical results presented. Analytically predicted results for cooled blade performance are compared to experimental results. The problems and some of the current programs associated with the use of very high work factors for fan-drive turbines of high-bypass-ratio engines are discussed. Turbines currently being investigated make use of advanced blading concepts designed to maintain high efficiency under conditions of high aerodynamic loading. Computer programs have been developed for turbine design-point performance, off-design performance, supersonic blade profile design, and the calculation of channel velocities for subsonic and transonic flow fields. The use of these programs for the design and analysis of axial and radial turbines is discussed

Classical generalized constant coupling model for geometrically frustrated antiferromagnets

A generalized constant coupling approximation for classical geometrically frustrated antiferromagnets is presented. Starting from a frustrated unit we introduce the interactions with the surrounding units in terms of an internal effective field which is fixed by a self consistency condition. Results for the magnetic susceptibility and specific heat are compared with Monte Carlo data for the classical Heisenberg model for the pyrochlore and kagome lattices. The predictions for the susceptibility are found to be essentially exact, and the corresponding predictions for the specific heat are found to be in very good agreement with the Monte Carlo results.Comment: 4 pages, 3 figures, 2 columns. Discussion about the zero T value of the pyrochlore specific heat correcte

Strengthening health technology assessment systems in the global south: a comparative analysis of the HTA journeys of China, India and South Africa.

BACKGROUND: Resource allocation in health is universally challenging, but especially so in resource-constrained contexts in the Global South. Pursuing a strategy of evidence-based decision-making and using tools such as Health Technology Assessment (HTA), can help address issues relating to both affordability and equity when allocating resources. Three BRICS and Global South countries, China, India and South Africa have committed to strengthening HTA capacity and developing their domestic HTA systems, with the goal of getting evidence translated into policy. Through assessing and comparing the HTA journey of each country it may be possible to identify common problems and shareable insights. OBJECTIVES: This collaborative paper aimed to share knowledge on strengthening HTA systems to enable enhanced evidence-based decision-making in the Global South by: Identifying common barriers and enablers in three BRICS countries in the Global South; and Exploring how South-South collaboration can strengthen HTA capacity and utilisation for better healthcare decision-making. METHODS: A descriptive and explorative comparative analysis was conducted comprising a Within-Case analysis to produce a narrative of the HTA journey in each country and an Across-Case analysis to explore both knowledge that could be shared and any potential knowledge gaps. RESULTS: Analyses revealed that China, India and South Africa share many barriers to strengthening and developing HTA systems such as: (1) Minimal HTA expertise; (2) Weak health data infrastructure; (3) Rising healthcare costs; (4) Fragmented healthcare systems; and (5) Significant growth in non-communicable diseases. Stakeholder engagement and institutionalisation of HTA were identified as two conducive factors for strengthening HTA systems. CONCLUSION: China, India and South Africa have all committed to establishing robust HTA systems to inform evidence-based priority setting and have experienced similar challenges. Engagement among countries of the Global South can provide a supportive platform to share knowledge that is more applicable and pragmatic

Evidence-informed capacity building for setting health priorities in low- and middle-income countries: : A framework and recommendations for further research

Priority-setting in health is risky and challenging, particularly in resource-constrained settings. It is not simply a narrow technical exercise, and involves the mobilisation of a wide range of capacities among stakeholders – not only the technical capacity to “do” research in economic evaluations. Using the Individuals, Nodes, Networks and Environment (INNE) framework, we identify those stakeholders, whose capacity needs will vary along the evidence-to-policy continuum. Policymakers and healthcare managers require the capacity to commission and use relevant evidence (including evidence of clinical and cost-effectiveness, and of social values); academics need to understand and respond to decision-makers’ needs to produce relevant research. The health system at all levels will need institutional capacity building to incentivise routine generation and use of evidence. Knowledge brokers, including priority-setting agencies (such as England’s National Institute for Health and Care Excellence, and Health Interventions and Technology Assessment Program, Thailand) and the media can play an important role in facilitating engagement and knowledge transfer between the various actors. Especially at the outset but at every step, it is critical that patients and the public understand that trade-offs are inherent in priority-setting, and careful efforts should be made to engage them, and to hear their views throughout the process. There is thus no single approach to capacity building; rather a spectrum of activities that recognises the roles and skills of all stakeholders. A range of methods, including formal and informal training, networking and engagement, and support through collaboration on projects, should be flexibly employed (and tailored to specific needs of each country) to support institutionalisation of evidence-informed priority-setting. Finally, capacity building should be a two-way process; those who build capacity should also attend to their own capacity development in order to sustain and improve impact

Identification of publicly available data sources to inform the conduct of Health Technology Assessment in India

Background: Health technology assessment (HTA) provides a globally-accepted and structured approach to synthesising evidence for cost and clinical effectiveness alongside ethical and equity considerations to inform evidence-based priorities. India is one of the most recent countries to formally commit to institutionalising HTA as an integral component of the heath resource allocation decision-making process. The effective conduct of HTA depends on the availability of reliable data. Methods: We draw from our experience of collecting, synthesizing, and analysing health-related datasets in India and internationally, to highlight the complex requirements for undertaking HTA, and explore the availability of such data in India. We first outlined each of the core data components required for the conduct of HTA, and their availability in India, drawing attention to where data can be accessed, and different ways in which researchers can overcome the challenges of missing or low quality data. Results: We grouped data into the following categories: clinical efficacy; cost; epidemiology; quality of life; service use/consumption; and equity. We identified numerous large local data sources containing epidemiological information. There was a marked absence of other locally-collected data necessary for informing HTA, particularly data relating to cost, service use, and quality of life. Conclusions: The introduction of HTA into the health policy space in India provides an opportunity to comprehensively assess the availability and quality of health data capture across the country. While epidemiological information is routinely collected across India, other data inputs necessary for HTA are not readily available. This poses a significant bottleneck to the efficient generation and deployment of HTA into the health decision space. Overcoming these data gaps by strengthening the routine collection of comprehensive and verifiable health data will have important implications not only for embedding economic analyses into the priority setting process, but for strengthening the health system as a whole

Keck Adaptive Optics Imaging of 0.5<z<1 Field Galaxies from the Hubble Space Telescope Archive

We have employed natural guide star adaptive optics (AO) on the Keck II telescope to obtain near-infrared (H and K') images of three field galaxies, each of redshift greater than 0.5. These are among the highest-redshift non-active disk galaxies to be imaged with AO. Each of the galaxies was chosen because it had been observed previously with the Hubble Space Telescope (HST) Wide Field Planetary Camera 2 (WFPC2) by others. Our AO images in the near infrared (NIR) closely match both the depth and high spatial resolution of those optical data. Combining the archival V and I data with our new H and K' images potentially produces a long wavelength baseline at uniform resolution. The NIR data probe emission well longward of the 4000-Angstrom break at these redshifts, and provide stellar fluxes less contaminated by dust. We fit two-dimensional galaxy bulge-plus-disk models simultaneously in all bands, and compare stellar-population-synthesis modeling to the photometry of these separated components. This is an initial foray into combining HST and AO imaging to produce a high spatial-resolution multi-color dataset for a large sample of faint galaxies. Our pilot program shows that NIR AO images from large ground-based observatories, augmented by HST images in the optical, can in principle provide a powerful tool for the analysis of faint field galaxies. However, the AO data S/N will have to be increased, and AO PSFs need to be controlled more carefully than they were here.Comment: 22 pages, 16 Postscript figures. Accepted for publication in the ApJ Supplement