NASA Scientific and Technical Aerospace Reports

20060001245 Institute of Space Medico-Engineering, Beijing, China
Progress in Research of Vascular Contractility under Weightlessness or Simulated Weightlessness
Li, Zhi-li; Jiang, Shi-zhong; Space Medicine & Medical Engineering; October 2005, pp. 387-390; In English; See also
20060001234; Copyright; Avail.: Other Sources
Weightlessness or simulated weightlessness-induced orthostatic intolerance appears to be due, in part, to the change of
vascular contractility. The functions of vessels are close to blood pressure, vessels structure and blood flow. The vessels have
respective structural and functional characteristics due to their different anatomic regions. The cephalic fluid shift and
elimination of the head-to-foot hydrostatic pressure gradient in weightlessness or simulated weightlessness may induce
adaptations of the vessels, which are different in property and degree. This review summarizes recent researches about these
adaptations to weightlessness or simulated weightlessness.
Author
Cardiovascular System; Blood Pressure; Weightlessness; Pressure Vessels; Hydrostatic Pressure; Blood Flow; Contraction
20060002051 Civil Aerospace Medical Inst., Oklahoma City, OK, USA, Ohio State Univ., Columbus, OH, USA
Medical Surveillance Programs for Aircraft Maintenance Personnel Performing Nondestructive Inspection and Testing
Nakagawara, V. B.; Montgomery, R. W.; Good, G. W.; November 2005; 14 pp.; In English; Original contains black and white
illustrations
Report No.(s): DOT/FAA/AM-05/21; No Copyright; Avail.: CASI: A03, Hardcopy
Visual inspection and nondestructive inspection and testing (NDI/NDT) are performed routinely to ensure that aircraft are
maintained in safe operating condition. Inspectors must make critical judgments about the condition of aircraft and aircraft
components using their eyes, basic visual aids (magnifiers, mirrors, and flashlights), and complicated NDI/NDT techniques
to detect anomalies. Failure to detect observable defects has been implicated in several aviation accidents. This study examines
the medical surveillance programs employed by aircraft maintenance facilities in the USA, indicating specific vision standards
and tests used for inspection personnel. We interviewed medical surveillance program personnel from nine major aircraft
maintenance facilities and repair stations by phone or in person. The current vision standards for inspectors at each of the
facilities surveyed were extracted from internal facility documents. Additionally, we reviewed the vision screening tests used
for medical surveillance of inspection personnel. There were differences in the vision standards for near vision (Snellen 20/20
and 20/25, Jaeger #1 and #2, Ortho Rater #8) distant vision (20/25, 20/30, none), color vision (distinguish and differentiate
contrast among colors, colors in the methods, normal color vision), and test intervals (annual, 2-year) at the facilities surveyed.
Vision screening tests used in the medical surveillance programs at these facilities were equally diverse, including choice of
vision screening tests. Medical surveillance programs for the aircraft maintenance facilities we surveyed different considerably
for both vision standards and screening tests used to evaluate performance of inspectors. The use of uniform vision standards
and test methods would provide quality control and facilitate a more accurate evaluation of the visual capabilities for
inspection personnel.
Author (revised)
Aircraft Maintenance; Snellen Tests; Nondestructive Tests; Surveillance
20060002347 Royal Netherlands Meteorological Inst., Netherlands
Results of and Adjustments to a Dynamic Vision Test
Bos, J. E.; Hogervorst, M. A.; July 2005; 26 pp.; In English; Original contains color illustrations
Report No.(s): TNO-DV3 2005 A058; TD2005-058; Copyright; Avail.: Other Sources
Previous studies showed that assessment of the dynamic visual acuity is of value in testing pilots, and how such a test
could be performed. It was, however, not known how this test would work in practice. When applied, it is essential that for
a normal population a reduction in acuity depending on the chosen stimuli can be realised, such that defects can be quantified
by the (reduced) amount of motion needed to cause a certain reduction in acuity. We applied the flash-test to four subjects
using the TNO 3D rotation chair with a CRT screen mounted on it in an extensive series of experiments. Results With moving
visual stimuli, the chosen test conditions sufficed to show a reduction in acuity. With self motion, however, we could not show
this. It is sufficient to measure the dynamic acuity by the flash test with a direct view on the CRT. It is sufficient too to apply
visual stimuli moving not faster than 32"/s. Passive self motion seems insufficient to measure the dynamic acuity. An
active auto rotation test seems the best alternative. Low frequency passive self rotation is needed to study fixation suppression
effects. The effect of ambient light and background characteristics seems negligible in all conditions. The previously proposed
test battery can therefore be reduced considerably. With a number of amendments, this test deserves to be applied to a group
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