NASA Scientific and Technical Aerospace Reports

esearchers will send to the ISS aboard the shuttle. With hoth, scientists hope to gain insight into how space travel might affect
astronauts genes.
Author
Gene Expression; Microgravity
20040068281 Lawrence Livermore National Lab., Livermore, CA
Individual Radiation Protection Monitoring in the Marshall Islands: Enewtak Island Resettlement Support (May-
December 2001)
Hamilton, T.; Hickman, D.; Conrado, C.; Brown, T.; Brunk, J.; Jun. 01, 2002; In English
Report No.(s): DE2003-15004810; UCRL-LR-149601; No Copyright; Avail: National Technical Information Service (NTIS)
The US Department of Energy (DOE) has recently implemented a series of strategic initiatives to address long-term
radiological surveillance needs at former US test sites in the Marshall Islands. The plan is to engage local atoll communities
in developing shared responsibilities for implementing radiation protection programs for resettled and resettling populations.
Using pooled resources of the US Department of Energy and local atoll governments, individual radiation protection programs
have been developed in whole-body counting and plutonium urinalysis to assess potential intakes of radionuclides from
residual fallout contamination. The whole-body counting systems are operated and maintained by Marshallese technicians.
Samples of urine are collected from resettlement workers and island residents under controlled conditions and analyzed for
plutonium isotopes at the Lawrence Livermore National Laboratory using advanced accelerator based measurement
technologies. This web site provides an overview of the methodologies, a full disclosure of the measurement data, and a yearly
assessment of estimated radiation doses to resettlement workers and island residents
NTIS
Dosage; Radioactive Isotopes; Radiation Detectors; Radiation Protection
20040068283 NASA Ames Research Center, Moffett Field, CA, USA
Single-Trial Characterization of Evoked Responses: Bayesian Estimation and Differentially Variable Component
Analysis
Knuth, Kevin H.; [2004]; 1 pp.; In English; EPIC XIV Meeting, 28-31 Mat. 2004, Leipzig, Germany; No Copyright; Avail:
Other Sources; Abstract Only
Brain responses are dynamic, state dependent, and change over time. In acknowledging this, it is becoming increasingly
more important to characterize single trial responses. Using Bayesian probability theory, I demonstrate how a more complex
signal model that accounts for amplitude and latency variability in the single trial allows one to characterize and examine
single trial responses. Furthermore, the fact that different neural ensembles exhibit differential variability patterns allows one
to tease apart these mixed signals and isolate signals generated from different neural ensembles. This new technique, called
differentially Variable Component Analysis (dVCA) allows one to separate, identify, and characterize single trial responses
from simultaneously active sources. Interactions among the ensembles can be studied by examining their single trial
properties. I will demonstrate the technique using simulations as well as intracortical field potentials recorded from a linear
multi-electrode array in a macaque experiencing visual stimulation.
Author
Bayes Theorem; Brain; Signal Analysis
20040070835 NASA Stennis Space Center, Bay Saint Louis, MS, USA
Software for Preprocessing Data from Rocket-Engine Tests
Cheng, Chiu-Fu; [2004]; 1 pp.; In English
Report No.(s): NASA/NP-2002-06-00023; SSC-00151; SSC-00153; SSC-00160; No Copyright; Avail: CASI; A01, Hardcopy
Three computer programs have been written to preprocess digitized outputs of sensors during rocket-engine tests at
Stennis Space Center (SSC). The programs apply exclusively to the SSC E test-stand complex and utilize the SSC file format.
The programs are the following: Engineering Units Generator (EUGEN) converts sensor-output-measurement data to
engineering units. The inputs to EUGEN are raw binary test-data files, which include the voltage data, a list identifying the
data channels, and time codes. EUGEN effects conversion by use of a file that contains calibration coefficients for each
channel. QUICKLOOK enables immediate viewing of a few selected channels of data, in contradistinction to viewing only
after post-test processing (which can take 30 minutes to several hours depending on the number of channels and other test
parameters) of data from all channels. QUICKLOOK converts the selected data into a form in which they can be plotted in
engineering units by use of Winplot (a free graphing program written by Rick Paris). EUPLOT provides a quick means for
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