Report of the Nuclear Propulsion Mission Analysis, Figures of Merit Subpanel: Quantifiable figures of merit for nuclear thermal propulsion

The results of an inquiry by the Nuclear Propulsion Mission Analysis, Figures of Merit subpanel are given. The subpanel was tasked to consider the question of what are the appropriate and quantifiable parameters to be used in the definition of an overall figure of merit (FoM) for Mars transportation system (MTS) nuclear thermal rocket engines (NTR). Such a characterization is needed to resolve the NTR engine design trades by a logical and orderly means, and to provide a meaningful method for comparison of the various NTR engine concepts. The subpanel was specifically tasked to identify the quantifiable engine parameters which would be the most significant engine factors affecting an overall FoM for a MTS and was not tasked with determining 'acceptable' or 'recommended' values for the identified parameters. In addition, the subpanel was asked not to define an overall FoM for a MTS. Thus, the selection of a specific approach, applicable weighting factors, to any interrelationships, for establishing an overall numerical FoM were considered beyond the scope of the subpanel inquiry

Feasibility analysis of cislunar flight using the Shuttle Orbiter

A first order orbital mechanics analysis was conducted to examine the possibility of utilizing the Space Shuttle Orbiter to perform payload delivery missions to lunar orbit. In the analysis, the earth orbit of departure was constrained to be that of Space Station Freedom. Furthermore, no enhancements of the Orbiter's thermal protection system were assumed. Therefore, earth orbit insertion maneuvers were constrained to be all propulsive. Only minimal constraints were placed on the lunar orbits and no consideration was given to possible landing sites for lunar surface payloads. The various phases and maneuvers of the mission are discussed for both a conventional (Apollo type) and an unconventional mission profile. The velocity impulses needed, and the propellant masses required are presented for all of the mission maneuvers. Maximum payload capabilities were determined for both of the mission profiles examined. In addition, other issues relating to the feasibility of such lunar shuttle missions are discussed. The results of the analysis indicate that the Shuttle Orbiter would be a poor vehicle for payload delivery missions to lunar orbit

The importance of qualitative methods for generating patient reported outcome measures and patient reported experience measures for pre-hospital and emergency care of stroke and heart attack

Context: The Patient Reported Outcomes for Vascular Emergencies: Interview Study (IS-PROVE) of patients and practitioners was conducted in a large regional ambulance service in the East Midlands region of the UK from 2010-2011. The aim of the study was to explore the experiences of patients and practitioners for emergency care of stroke or heart attack in the pre-hospital setting. Problem: Current health policy emphasises patient experience, together with effectiveness and safety, as key components of quality of care. As a consequence, patient reported outcome measures (PROMs) and patient reported experience measures (PREMs) are increasingly being seen as important, whether by providers, commissioners, regulators or service users themselves for assessing quality of care, by researchers for evaluating the outcomes of specific interventions and also clinicians for assessment and decision support. Despite the introduction of PROMs into the NHS in 2009 there are few validated PROMs in use or under development in the field of urgent (or emergency) care. Assessment of problem and analysis of its causes: We identified an important need to develop PROMs/PREMs for pre-hospital stroke and heart attack care and undertook the initial steps to develop appropriate item content for inclusion in such instruments. Patients that had suffered from these conditions and Practitioners that treated these conditions in the pre-hospital setting participated in qualitative interviews in order to obtain rich, in depth data. Intervention: Data were analysed with the support of Nvivo software and coded before final items for inclusion in the PROM/PREM were agreed by the research team. The PROMs and PREMs have been refined following elaboration of individual items and the next stage will involve formal testing and modification of the (construct) validity, reliability and responsiveness of the instruments. Study design: We used a qualitative design; individual interviews were conducted with patients or practitioners. Participants were also given the opportunity to take part in a focus group if they preferred. The benefits of focus groups are that they enable a range of experiences, beliefs, views and feelings to be explored in a setting of mutual understanding Strategy for change: The PROM and PREM tools for stroke and heart attack that we have developed will be piloted by ambulance clinicians that routinely treat these conditions to assess their validity and feasibility in the setting. We envisage that the tool will enable us to quantify patient reported outcome measure scores and examine the effects of organisational changes on patient outcomes. Measurement of improvement: The initial themes that emerged from the qualitative interviews and focus groups have included aspects such as reassurance, confidence in paramedic abilities, professional persona of clinicians and timeliness of service. These have allowed us to obtain a more informed understanding of the issues that patients attach greatest importance to in the pre-hospital setting. Effects of changes: We will use the PROM and PREM tools to assess the quality of care for patients with stroke and heart attack presenting to ambulance services. This will enable the regular monitoring of care standards and identify areas for improvement. Lessons learnt: We acquired new first hand knowledge from patients about their experiences of using the ambulance service for stroke and heart attack as well as learning about the issues that pre-hospital clinicians felt were important for improving care. Message for others: Development of PROMs and PREMs will be important for evaluating health care services and improving the quality of care. The methods used in this study may be useful for the development of PROMs in other settings

A Young Planetary-Mass Object in the ρ Oph Cloud Core

We report the discovery of a young planetary-mass brown dwarf in the ρ Oph cloud core. The object was identified as such with the aid of a 1.5-2.4 μm low-resolution spectrum obtained using the NIRC instrument on the Keck I telescope. Based on the COND model, the observed spectrum is consistent with a reddened (A_V ~ 15-16) brown dwarf whose effective temperature is in the range 1200-1800 K. For an assumed age of 1 Myr, comparison with isochrones further constrains the temperature to ~1400 K and suggests a mass of ~2-3 Jupiter masses. The inferred temperature is suggestive of an early T spectral type, which is supported by spectral morphology consistent with weak methane absorption. Based on its inferred distance (~100 pc) and the presence of overlying visual absorption, it is very likely to be a ρ Oph cluster member. In addition, given the estimated spectral type, it may be the youngest and least massive T dwarf found so far. Its existence suggests that the initial mass function for the ρ Oph star-forming region extends well into the planetary-mass regime

On the Leading Error Term of Exponentially Fitted Numerov Methods

Second-order boundary value problems are solved with exponentially-fitted Numerov methods. In order to attribute a value to the free parameter in such a method, we look at the leading term of the local truncation error. By solving the problem in two phases, a value for this parameter can be found such that the tuned method behaves like a sixth order method. Furthermore, guidelines to choose between multi le possible values for this parameter are given

A re-examination of the Salicornias (Amaranthaceae) of Saudi Arabia and their polymorphs

During the period from 1964 to 1999 Saudi Arabian species of Salicornia were wrongly treated under the European species, S. europaea L. Recent explorations proved that there are two separate allopatric species of Salicornia in Saudi Arabia, one inhabiting the inland salt-marshes of the Najd (highlands) and the other inhabiting the Arabian Gulf Coast (lowlands). Morphological, ecological and exploratory studies confirm that they are two distinct species. The two species differ in features of bark, axillary spikes, basal vegetative segment(s) of spike, fertile segments, colour of senescent plants, and flowering, fruiting and germination phenology. As both the species have been described earlier from Iran, they are now new records for Saudi Arabia. The species are, S. persica ssp. iranica (Akhani) Kadereit & Piirainen and S. sinus-persica Akhani. S. sinus-persica, of which the status was thought doubtful has been confirmed. Both the species have been described and illustrated. Each species comprises a number of polymorphs. As leaves and flowers are rudimentary, confusing species circumscriptions, a proliferation of binomials has resulted in the taxonomy of Salicornia. To mitigate such confusion, the full range of variability of the Saudi Arabian species has been documented

Investigation of aerothermodynamics and optical radiation in the AFE hypersonic flow field

Research for the radiation experiments on the Aeroassist Flight Experiment (AFE) was performed to obtain a data base for development of engineering requirements for aerobrakes. Due to funding restrictions, the necessary Aerobrake design data were obtained from ground based experiments, specifically arc-jet wind tunnels. Except for the instrument windows, final development of the AFE radiometers was completed. Window definition included several designs to be flight validated in arc-jets. This work was completed, and successful designs have evolved which will yield full scientific return from the flight experiment. The theoretical work includes final code development to describe the spacecraft environment to support instrument definition, optical radiation codes that operate at significantly improved speeds, and calculation of radiation forebody loads and effects on experiment objectives for varying AFE weights and trajectories. Furthermore, radiant flux vectors at the AFE base were predicted to be used for afterbody instrument definition. The Vacuum Ultraviolet Experiment for the Arc-Jet was completed, and arc-jet experiment conditions and experiment objectives were refined to incorporate the most current thinking. Ballistic range experiments were completed. Several shadowgraphs indicating corner turning angles and waviness structures were obtained, and the results were used to estimate the compression region location for the AFE flight. The waviness measured has helped to model the temporal variations of wake radiation for purposes of defining radiometers to measure the energy content of wake dynamics

A case study framework for design and evaluation of a national project to improve prehospital care of myocardial infarction and stroke

Background: Cardiovascular disease (CVD) affects 1.8% of the population annually, 0.9% with stroke and 0.8% with coronary heart disease. People suffering from CVD often present acutely to ambulance services with symptoms of acute myocardial infarction or stroke. Early and effective treatment prevents death, improves long term health and reduces future disability. Objective: Our aim is to develop a rational approach for informing the design and evaluation of a national project for improving prehospital care of myocardial infarction and stroke: the Ambulance Services Cardiovascular Quality Initiative (ASCQI), the first national improvement project for prehospital care. Methods: We will use a case study methodology initially utilising an evaluation logic model to define inputs (in terms of resources for planning, implementation and evaluation), outputs (in terms of intended changes in healthcare processes) and longer-term outcomes (in terms of health and wider benefits or harms), whether intended or incidental and in the short, medium or long term. Results: We will present an evaluation logic model for the project. This will be expanded to show the analytical techniques which we will use to explain how and why the project achieves its outcomes. This includes times series analyses, pattern matching, cross case syntheses and explanation building to inform an explanatory logic model. We will discuss how this model will be useful in determining the data that will need to be collected during the course of the project to inform the detailed explanation of how and why the project delivered its outcomes. Conclusion: The case study approach will enable us to evaluate the impact of this collaborative project in constituent ambulance services as well as the initiative as a whole. It will enable us to show whether and to what extent the project has had an impact, but also how and why this has happened

The Blot in Recruit Training

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