294 research outputs found
A STUDY OF HUMAN PILOTS' ABILITY TO DETECT ANGULAR MOTION WITH APPLICATION TO CONTROL OF SPACE RENDEZVOUS
Angular motion detection by human pilots and application to space rendezvous contro
Cable arrangement for rigid tethering Patent
Force separation rigid tethering device using cable
The longitudinal thickness of air-shower fronts
Linsely (1983) has proposed a technique for the detection and analysis of air showers at large distances from the shower axis based on a measurement of the shower front thickness and the assumption that this thickness is closely related to the core distance. Some of the problems involved with realizing such a technique were investigated, and some related observations are reported. The practical problems of how consistent the measurements of the shower front would be, how one would use the measurement, and how the rate of triggered events would depend on the minimum pulse width required are studied
The Weak Blue Bump of H2106-099 and AGN De-Reddening
We present multi-frequency spectra of the Seyfert 1 galaxy H2106-099, from
radio to hard X-rays, spanning over a decade of observations. The hard X-ray
(2-20 keV) spectrum measured with Ginga had a Log slope of -0.80 +/- 0.02 on
1988 May 18 and -1.02 +/- 0.10 on 1988 May 22 / 23 UT, with no observed flux
changes. Other measurements showed variability and unusual spectral features:
The V band flux changed by a factor of 1.8 (> 10 sigma) in six weeks. Only
moderate optical Fe II emission is present, but strong [FeVII] and [Fe X] lines
are present in some epochs. The Balmer lines show > 25% variations in flux
relative to the mean, and He I changed by more than 100% relative to the mean
in <~ six years. The most surprising finds came from the composite UV through
near-IR spectrum: If the spectrum is de-reddened by the galactic extinction
value (from 21 cm observations), a residual 2175 Angstrom absorption feature is
present. Additional de-reddening to correct the feature yields E(B-V)=0.07 mag
due to material outside our galaxy, most probably associated with the AGN or
its host galaxy. No other clear indications of reddening are observed in this
object, suggesting that blue bump strength measurements in low and intermediate
red-shift AGN could be incorrect if derived without UV observations of the
region near 2175 Angstrom in the AGN frame. After all reddening corrections are
performed, the log slope of H2106-099 from the near IR (~12500 Angstrom) to the
UV (~1400 Angstrom), -0.94 +/- 0.05, is steep compared to other AGN, suggesting
that the blue bump in this object is intrinsically weak. Weak blue bumps are,
therefore, not always an artifact caused by reddening.Comment: Three parts: A. 33 pages text, B. one landscape table, C. 8 figure
VETA-I x ray test analysis
This interim report presents some definitive results from our analysis of the VETA-I x-ray testing data. It also provides a description of the hardware and software used in the conduct of the VETA-I x-ray test program performed at the MSFC x-ray Calibration Facility (XRCF). These test results also serve to supply data and information to include in the TRW final report required by DPD 692, DR XC04. To provide an authoritative compendium of results, we have taken nine papers as published in the SPIE Symposium, 'Grazing Incidence X-ray/EUV Optics for Astronomy and Projection Lithography' and have reproduced them as the content of this report
VETA x ray data acquisition and control system
We describe the X-ray Data Acquisition and Control System (XDACS) used together with the X-ray Detection System (XDS) to characterize the x-ray image during testing of the AXAF P1/H1 mirror pair at the MSFC X-ray Calibration Facility. A variety of x-ray data were acquired, analyzed, and archived during the testing including: mirror alignment, encircled energy, effective area, point spread function, system housekeeping, and proportional counter window uniformity data. The system architecture will be presented with emphasis placed on key features that include a layered UNIX tool approach, dedicated subsystem controllers, real-time X-window displays, flexibility in combining tools, network connectivity, and system extensibility. The VETA test data archive are also described
Reported fatigue in people after Guillain-Barré Syndrome: a retrospective national survey in the UK
Aim. Despite continuing functional recovery over time, fatigue remains a persistent feature of post-acute GuillainBarré Syndrome (GBS). The aim of this study was to determine the prevalence of fatigue in people after GBS and investigate its associations with other factors after GBS. Methods. Validated questionnaires including the SF-36 and fatigue severity scale were sent to members of the GBS support group, a UK wide patient and carer organisation. Results. A total of 884 questionnaires were returned (58% response rate). Respondents’ answers demonstrated that those with severe fatigue following GBS had spent longer in hospital than those who were not severely fatigued (P=0.003). Poorer mental health was also associated with more severe fatigue. A strong predictor of prolonged fatigue was discharge from hospital in a wheelchair (OR=2.37, 95% CI 1.52 to 3.71, P<0.001) but the severity of fatigue appeared to be independent of recovery of mobility (Kendall’s taub=0.03, P=0.2). Conclusion. This survey is the largest study of fatigue in people after GBS. Its findings demonstrate that fatigue remains a persistent problem for many people after GBS. More severe fatigue was associated with decreased health related quality of life and increased levels of depression and anxiety in people after GBS. Whilst the severity of fatigue was significantly associated with poorer mobility on discharge, there was no association between the recovery of mobility after discharge and fatigue severity. This indicates that whilst other impairments and activity limitations improved over time, fatigue did not and implies that more severe fatigue is not simply an indicator of a more severe presentation of GBS. Whilst the reasons for persistent severe fatigue remain unclear, this study indicates that further investigations of mobility, mental health and fatigue are warranted so that targeted interventions can be put in place to manage this debilitating complication. (It J Physiotherapy 2013;3:154-60
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