Stereo imaging velocimetry for microgravity applications

Stereo imaging velocimetry is the quantitative measurement of three-dimensional flow fields using two sensors recording data from different vantage points. The system described in this paper, under development at NASA Lewis Research Center in Cleveland, Ohio, uses two CCD cameras placed perpendicular to one another, laser disk recorders, an image processing substation, and a 586-based computer to record data at standard NTSC video rates (30 Hertz) and reduce it offline. The flow itself is marked with seed particles, hence the fluid must be transparent. The velocimeter tracks the motion of the particles, and from these we deduce a multipoint (500 or more), quantitative map of the flow. Conceptually, the software portion of the velocimeter can be divided into distinct modules. These modules are: camera calibration, particle finding (image segmentation) and centroid location, particle overlap decomposition, particle tracking, and stereo matching. We discuss our approach to each module, and give our currently achieved speed and accuracy for each where available

Sexual Harassment And Public Accounting: Anecdotal Evidence From The Profession

This article reports on anecdotal evidence gathered from a recent survey of women public accounting professionals.  Stanko and Schneider (1999) conducted the first national survey on sexual harassment in the public accounting profession and Stanko et al followed up with a more recent 2009 study.  In this paper, the anecdotal evidence gathered from the Stanko et al study is reported on. Analysis of written comments is important in that many respondents spent a great deal of time providing comprehensive and concise professional comments on specific recent experiences involving sexual harassment, rather than simply checking a box. The findings of this study show sexual harassment remains a serious concern, and that sexual discrimination in the workplace is a concern as well.  Although preventive measures have been put in place, these measures may not be working as well as intended, suggesting that public accounting firms need to revisit this issue to manage risk

Distinct phosphorylation clusters determines the signalling outcome of the free fatty acid receptor FFA4/GPR120

It is established that long-chain free fatty acids including ω-3 fatty acids mediate an array of biological responses through members of the free fatty acid receptor family, which includes FFA4. However, the signalling mechanisms and modes of regulation of this receptor class remain unclear. Here we employ mass spectrometry to determine that phosphorylation of mouse (m)FFAR4 occurs at five serine and threonine residues clustered in two separable regions of the C terminal tail, designated cluster 1 (Thr347, Thr349 and Ser350) and cluster 2 (Ser357 and Ser361). Mutation of these phospho-acceptor sites to alanine completely prevented phosphorylation of mFFA4 but did not limit receptor coupling to ERK1/2 activation. Rather an inhibitor of Gq/11 proteins completely prevented receptor signalling to ERK1/2. In contrast, the recruitment of arrestin 3, receptor internalization and activation of Akt were regulated by mFFA4 phosphorylation. The analysis of mFFA4 phosphorylation-dependent signalling was extended further by selective mutations of the phospho-acceptor sites. Mutations within cluster 2 did not affect agonist activation of Akt but instead significantly compromised receptor internalization and arrestin 3 recruitment. Distinctly, mutation of the phospho-acceptor sites within cluster 1 had no effect on receptor internalization and a less extensive effect on arrestin 3 recruitment, but significantly uncoupled the receptor from Akt activation. These unique observations define differential effects on signalling mediated by phosphorylation at distinct locations. This hallmark feature supports the possibility that the signalling outcome of mFFA4 activation can be determined by the pattern of phosphorylation (phosphorylation barcode) at the C-terminus of the receptor

Three-dimensional propagation effects near the mid-Atlantic Bight shelf break (L)

Significant three-dimensional (3-D) environmental variability exists in the vicinity of the shelf break along the mid-Atlantic Bight. This study examines the influence of azimuthal coupling due to this variability on acoustic propagation in this region. Numerical studies employing a 3-D ray code, a hybrid ray-mode code, and a 3-D parabolic equation model are used to study the significance of azimuthal coupling on various propagation paths. These paths include up-slope, slant-slope, and cross-slope propagation. The numerical analysis suggests that, for the propagation ranges less than 60 km examined, the influence of azimuthal coupling is negligible compared to the inherent uncertainty in the environment itself

The great American garage

Thesis (M. Arch.)--Massachusetts Institute of Technology, Dept. of Architecture, 2004.Includes bibliographical references.How does one explore the suburban home? Go in through the garage, of course. Sales, bands, suicides, and business startups: The suburban garage is the most culturally flexible space in the entire American domestic environment. In this flexibility, it stands opposed to many of the established notions of suburban domestic context. It is illustrative of the displayed, hidden, and forgotten wonders of the American home. Within the context of this thesis, established interpretations of the garage program are used in the form of metaphor and hyperbole to create differing typologies of the American home. The metaphors themselves have developed out of a very dense genealogy of American suburban histories and trajectories. They have a real history, just as they occupy a very real extant condition of the suburban context. The new suburban house typologies march toward the space of the surreal via the narratives that accompany each of them, allowing for an exploration into the existing domestic condition as well as a feverish and jocular critique of some of the norms of suburban life. The attempt of the research is to take on the exploration of American suburbia, using the very stereotypes and cliches that have come to define it.by B. Alex Miller.M.Arch

Conservation Status and Habitat Use of the West Virginia Spring Salamander (Gyrinophilus Subterraneus) and Spring Salamander (G. Porphyriticus) in General Davis Cave, Greenbrier Co., West Virginia

The West Virginia Spring Salamander (Gyrinophilus subterraneus) is one of four obligate cave-dwelling species of plethodontid salamanders found east of the Mississippi River in the United States. This species is endemic to a single cave system; General Davis Cave, in Greenbrier Co., West Virginia, where it is syntopic with the closely-related Spring Salamander (G. porphyriticus). Accordingly, the West Virginia Spring Salamander is a species of critical conservation concern. Because of it\u27s conservation status and lack of data regarding the ecology and life history, particularly about population trends, we present data on relative abundance of and habitat use by the West Virginia Spring Salamander during a 33-year period from 1975-2008. Specifically we address: (1) stability of the population during the last 33 years; (2) variation in habitat use by life stage and between species (Spring Salamanders and West Virginia Spring Salamanders); (3) plausibility of neoteny in the West Virginia Spring Salamander; and (4) the conservation status of the West Virginia Spring Salamander. We recorded 324 observations of Gyrinophilus salamanders, of which 192 were West Virginia Spring Salamanders, within the study area during 17 surveys. While both larval and metamorphosed West Virginia Spring Salamanders were encountered, only metamorphosed Spring Salamanders were observed. West Virginia Spring Salamander larvae were encountered in pools more often than in riffle habitat. Spring Salamanders were encountered more often in terrestrial habitats versus aquatic habitats. West Virginia Spring Salamanders reach relatively large size before metamorphosing, with some individuals becoming sexual mature as larvae. It remains unknown whether any of these individuals reproduce, however. Although the populations of both species appear to be stable over the past 33 years and not in immediate danger of extinction, the West Virginia Spring Salamander is still in critical conservation concern because of it\u27s extremely restricted distribution and current threats to the cave system it resides in

Architecting the Communication and Navigation Networks for NASA's Space Exploration Systems

NASA is planning a series of short and long duration human and robotic missions to explore the Moon and then Mars. A key objective of the missions is to grow, through a series of launches, a system of systems communication, navigation, and timing infrastructure at minimum cost while providing a network-centric infrastructure that maximizes the exploration capabilities and science return. There is a strong need to use architecting processes in the mission pre-formulation stage to describe the systems, interfaces, and interoperability needed to implement multiple space communication systems that are deployed over time, yet support interoperability with each deployment phase and with 20 years of legacy systems. In this paper we present a process for defining the architecture of the communications, navigation, and networks needed to support future space explorers with the best adaptable and evolable network-centric space exploration infrastructure. The process steps presented are: 1) Architecture decomposition, 2) Defining mission systems and their interfaces, 3) Developing the communication, navigation, networking architecture, and 4) Integrating systems, operational and technical views and viewpoints. We demonstrate the process through the architecture development of the communication network for upcoming NASA space exploration missions

Effect of Passive Horizontal Rotations and Vertical Oscillations on Dynamic Visual Acuity

Astronauts experience sensorimotor disturbances after long duration space flight. These crewmembers may need to egress the vehicle within a few minutes for safety and operational reasons in various sea state conditions following a water landing. Exposure to even low frequency motions induced by sea conditions surrounding a vessel can cause significant fine and gross motor control problems affecting critical functions. The objective of this study was to document human motor and visual performance during simulated wave motion in the 0.1 to 2.0 Hz range. We examined in 12 healthy subjects the changes in accuracy when performing a seated visual target acquisition task in which the location of target was offset vertically during horizontal full body rotation at an oscillating frequency of 0.8 Hz (peak velocity of 160 deg/s). The main finding was that the accuracy of performance degraded in 7 of 12 subjects when acquiring vertical targets at perturbing frequencies of 0.8 Hz in the horizontal plane by one step size. We also examined in a separate study on 12 healthy subjects seated dynamic visual acuity (DVA) task performance during vertical full body oscillations at perturbing frequencies of 2 Hz (peak to peak motion of 5 cm). The main finding was that DVA was significantly reduced when acquiring targets at perturbing oscillations at frequencies of 2 Hz in the vertical plane by approximately 1 chart line. Thus low frequencies of perturbations in the horizontal and vertical planes can cause decrement in visual performance

Spectroscopy and Reactivity of a Photogenerated Tryptophan Radical in a Structurally Defined Protein Environment

Near-UV irradiation of structurally characterized [Re(I)(CO)_3(1,10-phenanthroline)(Q107H)](W48F/Y72F/H83Q/Y108W)AzM(II) [Az = Pseudomonas aeruginosa azurin, M = Cu, Zn]/[Co(NH_3)_5Cl]Cl_2 produces a tryptophan radical (W108•) with unprecedented kinetic stability. After rapid formation (k = 2.8 × 10^6 s^(-1)), the radical persists for more than 5 h at room temperature in the folded ReAzM(II) structure. The absorption spectrum of ReAz(W108•)M(II) exhibits maxima at 512 and 536 nm. Oxidation of K_4[Mo(CN)_8] by ReAz(W108•)Zn(II) places the W108•/W108 reduction potential in the protein above 0.8 V vs NHE