50 Years of Spaceflight with Fourier Transform Spectrometers (FTS) Built at NASA GSFC

Over the past 50 years, NASA Goddard Space Flight Center (GSFC) has been developing, building, testing and flying a series of Fourier Transform Spectrometers (FTS). This began with the IRIS instruments on the Earth-orbiting Nimbus satellites and progressed to more sophisticated designs optimized for interplanetary spacecraft sent to Mars and later to the outer solar system. Adaptions have been made over time, including progressively higher spectral resolution, sensitivity, numbers of detectors and complexity. Instrument operating temperatures have decreased to enable remote sensing of the cold giant planet systems. In this paper we describe the historical evolution of this instrument line, comparing and contrasting different aspects such as optical design and materials, detector types and data handling. We conclude by looking towards the future. At present the CIRS-Lite prototype is being tested at NASA GSFC for potential use on a future mission to the ice giants, Uranus and Neptune. Surpassing the previous performance of the Voyager IRIS instruments remains challenging, and new technologies that could enable these measurements are discussed

Redesign of the Extravehicular Mobility Unit Airlock Cooling Loop Recovery Assembly

During EVA (Extravehicular Activity) 23 aboard the ISS (International Space Station) on 07/16/2013 an episode of water in the EMU (Extravehicular Mobility Unit) helmet occurred, necessitating a termination of the EVA (Extravehicular Activity) shortly after it began. The root cause of the failure was determined to be ground-processing short-comings of the ALCLR (Airlock Cooling Loop Recovery) Ion Beds which led to various levels of contaminants being introduced into the Ion Beds before they left the ground. The Ion Beds were thereafter used to scrub the failed EMU cooling water loop on-orbit during routine scrubbing operations. The root cause investigation identified several areas for improvement of the ALCLR Assembly which have since been initiated. Enhanced washing techniques for the ALCLR Ion Bed have been developed and implemented. On-orbit cooling water conductivity and pH analysis capability to allow the astronauts to monitor proper operation of the ALCLR Ion Bed during scrubbing operation is being investigation. A simplified means to acquire on-orbit EMU cooling water samples have been designed. Finally, an inherently cleaner organic adsorbent to replace the current lignite-based activated carbon, and a non-separable replacement for the separable mixed ion exchange resin are undergoing evaluation. These efforts are undertaken to enhance the performance and reduce the risk associated with operations to ensure the long-term health of the EMU cooling water circuit

'Working away in that Grey Area...' A qualitative exploration of the challenges general practitioners experience when managing behavioural and psychological symptoms of dementia

Background: general practitioners (GPs) have identified the management of behavioural and psychological symptoms of dementia (BPSD) as a particularly challenging aspect of dementia care. However, there is a paucity of research on why GPs find BPSD challenging and how this influences the care they offer to their patients with dementia. Objectives: to establish the challenges GPs experience when managing BPSD; to explore how these challenges influence GPs’ management decisions; and to identify strategies for overcoming these challenges. Design: qualitative study of GPs experiences of managing BPSD. Methods: semi-structured interviews were conducted with 16 GPs in the Republic of Ireland. GPs were purposively recruited to include participants with differing levels of experience caring for people with BPSD in nursing homes and in community settings to provide maximum diversity of views. Interviews were analysed thematically. Results: three main challenges of managing BPSD were identified; lack of clinical guidance, stretched resources and difficulties managing expectations. The lack of relevant clinical guidance available affected GPs’ confidence when managing BPSD. In the absence of appropriate resources GPs felt reliant upon sedative medications. GPs believed their advocacy role was further compromised by the difficulties they experienced managing expectations of family caregivers and nursing home staff. Conclusions: this study helps to explain the apparent discrepancy between best practice recommendations in BPSD and real-life practice. It will be used to inform the design of an intervention to support the management of BPSD in general practice

Performance and Life Tests of a Regenerative Blower for EVA Suit Ventilation

Ventilation fans for future space suits must meet demanding performance specifications, satisfy stringent safety requirements for operation in an oxygen atmosphere, and be able to increase output to operate in buddy mode. A regenerative blower is an attractive choice due to its ability to meet these requirements at low operating speed. This paper describes progress in the development and testing of a regenerative blower designed to meet requirements for ventilation subsystems in future space suits. The blower includes a custom-designed motor that has significantly improved its efficiency. We have measured the blower s head/flow performance and power consumption under conditions that simulate both the normal and buddy mode operating points. We have operated the blower for TBD hours and demonstrated safe operation in an oxygen test loop at prototypical pressures. We also demonstrated operation with simulated lunar dust

A Robust, Multisite Holocene History of Drift Ice off Northern Iceland: Implications for North Atlantic Climate

An important indicator of Holocene climate change is provided by evidence for variations in the extent of drift ice. A proxy for drift ice in Iceland waters is provided by the presence of quartz. Quantitative xray diffraction analysis of the \u3c 2 mm sediment fraction was undertaken on 16 cores from around Iceland. The quartz weight (wt.)% estimates from each core were integrated into 250-yr intervals between −0.05 and 11.7 cal. ka BP. Median quartz wt.% varied between 0.2 and 3.4 and maximum values ranged between 2.8 and 11.8 wt.%. High values were attained in the early Holocene and minimum values were reached 6–7 cal. ka BP. Quartz wt.% then rose steadily during the late Holocene. Our data exhibit no correlation with counts on haematite-stained quartz (HSQ) grains from VM129-191 west of Ireland casting doubt on the ice-transport origin. A pilot study on the provenance of Fe oxide grains in two cores that cover the last 1.3 and 6.1 cal. ka BP indicated a large fraction of the grains between 1 and 6 cal. ka BP were from either Icelandic or presently unsampled sources. However, there was a dramatic increase in Canadian and Russian sources from the Arctic Ocean ~1 cal. ka BP. These data may indicate the beginning of an Arctic Oscillation-like climate mode

A trans-Indian Ocean hydrographic section at latitude 32°South : data report of RRS Charles Darwin cruise #29

A trans-Indian Ocean hydrographic section employing CTD/O2 profilers was conducted between Africa and Australia during austral spring 1987. The cruise track ranged between 29°S and 34°S; the average latitude of the crossing was 32°S. The purpose of the cruise was to explore various aspects of the South Indian Ocean including the characteristics of the core water masses of this ocean, the strength of the subtropical gyre, the structure and transport of deep western-boundary currents, and the net meridional heat flux. A total of 109 CTD/O2 profiles with associated rosette water sample measurements and 347 XBT profiles were collected, supplemented by underway upper ocean velocity, bathymetric and sea surface temperature and salinity data. This report detals the data collection, calibration, and reduction methods, and summarizes the hydrographic observations.Funding was provided by the National Science Foundation through Grant No. OCE 86-14497

Perception of soundscapes : an interdisciplinary approach

This paper takes an overall view of findings from the Positive Soundscape Project, a large inter-disciplinary soundscapes study. Qualitative fieldwork (soundwalks and focus groups) have found that soundscape perception is influenced by cognitive effects such as the meaning of a soundscape and its components, and how information is conveyed by a soundscape, for example on the behaviour of people within the soundscape. Three significant clusters were found in the language people use to describe soundscapes: sound sources, sound descriptors and soundscape descriptors. Results from listening tests and soundwalks have been integrated to show that the two principal dimensions of soundscape emotional response seem to be calmness and vibrancy. Further, vibrancy seems to have two aspects: organisation of sounds and changes over time. The possible application of the results to soundscape assessment and design are briefly discussed

Systematic Analysis Method for Color Transparency Experiments

We introduce a data analysis procedure for color transparency experiments which is considerably less model dependent than the transparency ratio method. The new method is based on fitting the shape of the A dependence of the nuclear cross section at fixed momentum transfer to determine the effective attenuation cross section for hadrons propagating through the nucleus. The procedure does not require assumptions about the hard scattering rate inside the nuclear medium. Instead, the hard scattering rate is deduced directly from the data. The only theoretical input necessary is in modelling the attenuation due to the nuclear medium, for which we use a simple exponential law. We apply this procedure to the Brookhaven experiment of Carroll et al and find that it clearly shows color transparency: the effective attenuation cross section in events with momentum transfer $Q^2$ is approximately $40\ mb\ (2.2\ GeV^2/Q^2)$. The fit to the data also supports the idea that the hard scattering inside the nuclear medium is closer to perturbative QCD predictions than is the scattering of isolated protons in free space. We also discuss the application of our approach to electroproduction experiments.Comment: 11 pages, 11 figures (figures not included, available upon request), report # KU-HEP-92-2

Systems approach to creating test scenarios for automated driving systems

Increased safety has been advocated as one of the major benefits of the introduction of Automated Driving Systems (ADSs). Incorporation of ADSs in vehicles mean that associated software has safety critical application, thus requiring exhaustive testing. To prove ADSs are safer than human drivers, some work has suggested that they will need to be driven for over 11 billion miles. The number of test miles driven is not, by itself, a meaningful metric for judging the safety of ADSs. Rather, the types of scenarios encountered by the ADSs during testing are critically important. With a Hazard Based Testing approach, this paper proposes that the extent to which testing miles are ‘smart miles’ that reflect hazard-based scenarios relevant to the way in which an ADS fails or handles hazards is a fundamental, if not pivotal, consideration for safety-assurance of ADSs. Using Systems Theoretic Process Analysis (STPA) method as a foundation, an extension to the STPA method has been developed to identify test scenarios. The approach has been applied to a real-world case study of a SAE Level 4 Low-Speed Automated Driving system (a.k.a. a shuttle). This paper, discusses the STPA analysis and a newly-developed test scenarios creation method derived from STPA

A Randomized, Controlled Trial of Catheter-Related Infectious Event Rates Using Antibiotic-Impregnated Catheters Versus Conventional Catheters in Pediatric Cardiovascular Surgery Patients

We conducted a randomized, controlled clinical trial to determine whether a difference in catheter-associated blood stream infection (CABSI) incidence existed between children who underwent cardiac surgery and had a central venous catheter impregnated with minocycline and rifampin versus those who had a conventional, nonimpregnated catheter after cardiac surgery. Due to a lower number of infections than expected, the study was terminated early. Among 288 evaluable patients, the rates of CABSI and line-related complications were similar between the 2 groups