Technical aspects of a demonstration tape for three-dimensional sound displays

This document was developed to accompany an audio cassette that demonstrates work in three-dimensional auditory displays, developed at the Ames Research Center Aerospace Human Factors Division. It provides a text version of the audio material, and covers the theoretical and technical issues of spatial auditory displays in greater depth than on the cassette. The technical procedures used in the production of the audio demonstration are documented, including the methods for simulating rotorcraft radio communication, synthesizing auditory icons, and using the Convolvotron, a real-time spatialization device

Prestigious organizations and heterodox choice in institutionally plural contexts

In unsettled fields with multiple ideal-typical institutional logics, why do organizations tend to weaken or conform to prevalent logic order? We argue that prestige –defined as a tribute paid by field members to a select few with valued distinctive traits– plays a determinant role in explaining institutional heterodoxy (i.e., the choice to stop instantiating dominant logics or start instantiating less prevalent logics). In unsettled fields, prestigious organizations adopt institutional heterodoxy to maintain their distinctiveness because they consider logics as means rather than constraining ends and because awarding bodies cannot impose strict obedience rules. Controlling for alternative explanations, a study of 165 French industrial design agencies (1989 to 2003) provides evidence that prestige favors the decision to undertake heterodox choices. This relationship is weakened when organizations diversify their expertise, is marginally reinforced when organizations have high-status clients, and is influenced by peers' heterodox choices. We discuss contributions to the neo-institutional theory of organizational choices, the socio-cultural analysis of field's evolution, and the strategic perspective of the firm.agences de design, logiques institutionnelles, hétérodoxie

the role of shock waves in modulation of galactic cosmic rays

The understanding of modulation of the galactic cosmic rays has considerably progressed by the exploration by space probes of major heliospheric structures, such as the Corotating Interaction Regions, the neutral sheet, and the compression regions of intense heliospheric magnetic fields. Also relevant in this context were the detections in the outer heliosphere of long lasting Forbush type decreases of cosmic ray intensity. The results of recent theoretical studies on the changes in intensity and energy, at different location from the Sun, induced by the passage of shocks across the heliosphere are presented. In this version of the research, the simplest cases of modulation of uGV and 2GV particles by single or several shocks during periods of positive and negative solar field polarity are reviewed. The results of the theoretical aspects of the search is reported. The comparison of the theoretical predictions with space probe data allows conclusions to be drawn on the role of shocks on the modulation on both the 11 and 22 year galactic cosmic ray cycles in the outer heliosphere and on the plausibility of the models and parameters used

Effect of Whole-Body Vibration on Speech

The effect on speech intelligibility was measured for speech where talkers reading Diagnostic Rhyme Test material were exposed to 0.7 g whole body vibration to simulate space vehicle launch. Across all talkers, the effect of vibration was to degrade the percentage of correctly transcribed words from 83% to 74%. The magnitude of the effect of vibration on speech communication varies between individuals, for both talkers and listeners. A worst case scenario for intelligibility would be the most sensitive listener hearing the most sensitive talker; one participant s intelligibility was reduced by 26% (97% to 71%) for one of the talkers

Polyphenol alkyl ester inhibits membrane cholesterol domain formation through an antioxidant mechanism based, in nonlinear fashion, on chain length

Under conditions of oxidative stress, cholesterol aggregates into discrete membrane bilayer domains that precipitate the formation of extracellular crystals, a hallmark feature of the advanced atheroma in cardiovascular disease. Molecular intervention using membrane-directed antioxidants, such as polyphenolic esters, alkylated to increase their lipophilicity and bioavailability, may reduce cholesterol domain formation and associated pathology. In this study, we tested the effects of rosmarinic acid (R0) and rosmarinic esters, with alkyl chain lengths ranging from 4 to 16 carbons (R4-R16), on membrane lipid oxidation and cholesterol domain formation. Model membranes were prepared as binary mixtures of dilinoleoylphosphatidylcholine and cholesterol (at a cholesterol-to-phospholipid mole ratio of 0.6:1), in the absence or presence of each of the various rosmarinic compounds, and exposed to oxidative conditions for up to 72 hr. Changes in lipid hydroperoxide (LOOH) and cholesterol domain formation were measured using iodometric and small angle x-ray diffraction approaches, respectively. Rosmarinic acid and the various esters were observed to have differential effects on LOOH formation based on alkyl chain length. R8 had the greatest antioxidant effect, reducing LOOH levels by 60 ± 18% as compared to vehicle. R8 also inhibited cholesterol domain formation. By contrast, R0 and R16 failed to inhibit LOOH formation (6 ± 19% reduction, 5 ± 13% increase compared to vehicle, respectively), resulting in cholesterol domain formation. These data indicate that the membrane antioxidant potential of rosmarinic acid esters is dependent, in a nonlinear manner, on alkyl chain length. The mechanism for this effect is attributed to the influence of alkyl chain length on the optimal depth of the polyphenols into the lipid bilayer. These findings provide insight into novel atheroprotective benefits of polyphenol esters that are dependent on their membrane location

Quasiperiodicity and non-computability in tilings

We study tilings of the plane that combine strong properties of different nature: combinatorial and algorithmic. We prove existence of a tile set that accepts only quasiperiodic and non-recursive tilings. Our construction is based on the fixed point construction; we improve this general technique and make it enforce the property of local regularity of tilings needed for quasiperiodicity. We prove also a stronger result: any effectively closed set can be recursively transformed into a tile set so that the Turing degrees of the resulted tilings consists exactly of the upper cone based on the Turing degrees of the later.Comment: v3: the version accepted to MFCS 201

Identifying Arkansas Food Desert Blocks Suitable for a Peer-to-Peer Modeled Food Redistribution Program

Abstract Nearly 10% of Americans reside in low-income urban food deserts which are low-income areas that lack access to affordable and nutritious foods. Food deserts in Arkansas contribute to a food insecurity rate above the national average, making it one of the most food insecure states in the country. Increased internet usage and consumer interest in sharing based companies contribute to the idea of a sharing, or peer-to-peer (P2P) style food redistribution program. The objective of this study is to identify which of the 186,211census blocks in the state of Arkansas are food deserts and best suited for and in the most need, based on an identified set of criteria, of a P2P food redistribution program. A multi-criteria decision analysis was conducted using population, internet access, vulnerable communities, and vehicle availability as criteria. Results suggest that based upon the close proximity of priority areas, transportation access, ethnic/racial diversity, and the number of possible collection locations, Pulaski County be targeted for a P2P food redistribution pilot program

On the Representation Theory of Orthofermions and Orthosupersymmetric Realization of Parasupersymmetry and Fractional Supersymmetry

We construct a canonical irreducible representation for the orthofermion algebra of arbitrary order, and show that every representation decomposes into irreducible representations that are isomorphic to either the canonical representation or the trivial representation. We use these results to show that every orthosupersymmetric system of order $p$ has a parasupersymmetry of order $p$ and a fractional supersymmetry of order $p+1$.Comment: 13 pages, to appear in J. Phys. A: Math. Ge

Assessment and Mitigation of the Effects of Noise on Habitability in Deep Space Environments: Report on Non-Auditory Effects of Noise

This document reviews non-auditory effects of noise relevant to habitable volume requirements in cislunar space. The non-auditory effects of noise in future long-term space habitats are likely to be impactful on team and individual performance, sleep, and cognitive well-being. This report has provided several recommendations for future standards and procedures for long-term space flight habitats, along with recommendations for NASA's Human Research Program in support of DST mission success