22,343 research outputs found
Users manual for the Automated Performance Test System (APTS)
The characteristics of and the user information for the Essex Automated Performance Test System (APTS) computer-based portable performance assessment battery are given. The battery was developed to provide a menu of performance test tapping the widest possible variety of human cognitive and motor functions, implemented on a portable computer system suitable for use in both laboratory and field settings for studying the effects of toxic agents and other stressors. The manual gives guidance in selecting, administering and scoring tests from the battery, and reviews the data and studies underlying the development of the battery. Its main emphasis is on the users of the battery - the scientists, researchers and technicians who wish to examine changes in human performance across time or as a function of changes in the conditions under which test data are obtained. First the how to information needed to make decisions about where and how to use the battery is given, followed by the research background supporting the battery development. Further, the development history of the battery focuses largely on the logical framework within which tests were evaluated
Vacuum Alignment in Technicolor Theories-I. The Technifermion Sector
We have carried out numerical studies of vacuum alignment in technicolor
models of electroweak and flavor symmetry breaking. The goal is to understand
alignment's implications for strong and weak CP nonconservation in quark
interactions. In this first part, we restrict our attention to the
technifermion sector of simple models. We find several interesting phenomena,
including (1) the possibility that all observable phases in the technifermions'
unitary vacuum-alignment matrix are integer multiples of \pi/N' where N' \le N,
the number of technifermion doublets, and (2) the possibility of exceptionally
light pseudoGoldstone technipions.Comment: 19 pages, Latex with one postscript figur
The Thousand Aviator Study - Smoking history correlates of selected physiological, biochemical, and anthropometric measures
Smoking history correlates of selected physiological, biochemical, and anthropometric measure
Neutralization of chemokines RANTES and MIG increases virus antigen expression and spinal cord pathology during Theiler's virus infection.
The role of chemokines during some viral infections is unpredictable because the inflammatory response regulated by these molecules can have two, contrasting effects-viral immunity and immunopathologic injury to host tissues. Using Theiler's virus infection of SJL mice as a model of this type of disease, we have investigated the roles of two chemokines-regulated on activation, normal T cell-expressed and secreted (RANTES) chemokine and monokine induced by IFN-gamma (MIG)-by treating mice with antisera that block lymphocyte migration. Control, infected mice showed virus persistence, mild inflammation and a small degree of demyelination in the white matter of the spinal cord at 6 weeks post-infection. Treatment of mice with RANTES antiserum starting at 2 weeks post-infection increased both viral antigen expression and the severity of inflammatory demyelination at 6 weeks post-infection. MIG antiserum increased the spread of virus and the proportion of spinal cord white matter with demyelination. Overall, viral antigen levels correlated strongly with the extent of pathology. At the RNA level, high virus expression was associated with low IL-2 and high IL-10 levels, and RANTES antiserum decreased the IL-2/IL-10 ratio. Our results suggest that RANTES and MIG participate in an immune response that attempts to restrict viral expression while limiting immunopathology and that anti-chemokine treatment poses the risk of exacerbating both conditions in the long term
Trends in systolic blood pressure in the thousand aviator cohort over a 24-year period
Age, weight, and parental longevity effects on trends in systolic blood pressure in thousand aviator cohort over 24 year perio
A unique facility for V/STOL aircraft hover testing
The Langley Impact Dynamics Research Facility (IDRF) was modified to obtain static force and moment data and to allow assessment of aircraft handling qualities during dynamic tethered hover flight. Test probe procedures were also established. Static lift and control measurements obtained are presented along with results of limited dynamic tethered hover flight
Stability, reliability and cross-mode correlations of tests in a recommended 8-minute performance assessment battery
A need exists for an automated performance test system to study drugs, agents, treatments, and stresses of interest to the aviation, space, and environmental medical community. The purpose of this present study is to evaluate tests for inclusion in the NASA-sponsored Automated Performance Test System (APTS). Twenty-one subjects were tested over 10 replications with tests previously identified as good candidates for repeated-measure research. The tests were concurrently administered in paper-and-pencil and microcomputer modes. Performance scores for the two modes were compared. Data from trials 1 to 10 were examined for indications of test stability and reliability. Nine of the ten APT system tests achieved stability. Reliabilities were generally high. Cross-correlation of microbased tests with traditional paper-and-pencil versions revealed similarity of content within tests in the different modes, and implied at least three cognition and two motor factors. This protable, inexpensive, rugged, computerized battery of tests is recommended for use in repeated-measures studies of environmental and drug effects on performance. Identification of other tests compatible with microcomputer testing and potentially capable of tapping previously unidentified factors is recommended. Documentation of APTS sensitivity to environmental agents is available for more than a dozen facilities and is reported briefly. Continuation of such validation remains critical in establishing the efficacy of APTS tests
The Collider Phenomenology of Technihadrons in the Technicolor Straw Man Model
We discuss the phenomenology of the lightest SU(3)_C singlet and non-singlet
technihadrons in the Straw Man Model of low-scale technicolor (TCSM). The
technihadrons are assumed to be those arising in topcolor--assisted technicolor
models in which topcolor is broken by technifermion condensates. We improve
upon the description of the color--singlet sector presented in our earlier
paper introducing the TCSM (hep-ph/9903369). These improvements are most
important for subprocess energies well below the masses of the technirho and
techniomega, and, therefore, apply especially to e+e- colliders such as LEP and
a low--energy linear collider. In the color--octet sector, we consider mixing
of the gluon, the coloron V_8 from topcolor breaking, and four isosinglet
color--octet technirho mesons. We assume, as expected in walking technicolor,
that these technirhos decay into qbar-q, gg, and g-technipion final states, but
not into technipion pairs. All the TCSM production and decay processes
discussed here are included in the event generator Pythia. We present several
simulations appropriate for the Tevatron Collider, and suggest benchmark model
lines for further experimental investigation.Comment: 42 pages, 7 figure
Thermal and Non-thermal Plasmas in the Galaxy Cluster 3C 129
We describe new Chandra spectroscopy data of the cluster which harbors the
prototypical "head tail" radio galaxy 3C 129 and the weaker radio galaxy 3C
129.1. We combined the Chandra data with Very Large Array (VLA) radio data
taken at 0.33, 5, and 8 GHz (archival data) and 1.4 GHz (new data). We also
obtained new HI observations at the Dominion Radio Astrophysical Observatory
(DRAO) to measure the neutral Hydrogen column density in the direction of the
cluster with arcminute angular resolution. The Chandra observation reveals
extended X-ray emission from the radio galaxy 3C 129.1 with a total luminosity
of 1.5E+41 erg/s. The X-ray excess is resolved into an extended central source
of ~2 arcsec (1 kpc) diameter and several point sources with an individual
luminosity up to 2.1E+40 erg/s. In the case of the radio galaxy 3C 129, the
Chandra observation shows, in addition to core and jet X-ray emission reported
in an earlier paper, some evidence for extended, diffuse X-ray emission from a
region east of the radio core. The 12 arcsec x 36 arcsec (6 kpc x 17 kpc)
region lies "in front" of the radio core, in the same direction into which the
radio galaxy is moving. We use the radio and X-ray data to study in detail the
pressure balance between the non-thermal radio plasma and the thermal Intra
Cluster Medium (ICM) along the tail of 3C 129 which extends over 15 arcmin (427
kpc). Depending on the assumed lower energy cutoff of the electron energy
spectrum, the minimum pressure of the radio plasma lies a factor of between 10
and 40 below the ICM pressure for a large part of the tail. We discuss several
possibilities to explain the apparent pressure mismatch.Comment: Accepted for publication in MNRAS. Refereed manuscript. 14 pages, 8
figures, additional panel of Fig. 3 shows asymmetric ICM distributio
EC71-799 Engineering the Irrigation Pumping Plant
Extension Circular 71-799: Engineering the irrigation pumping plant; pumps selection, pump drives, setting up the drives, power units, and direction for matching an electric motor to an irrigation pump
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