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Potential Health Risks From Postulated Accidents Involving the Pu-238 RTG (Radioisotope Thermoelectric Generator) on the Ulysses Solar Exploration Mission (open access)

Potential Health Risks From Postulated Accidents Involving the Pu-238 RTG (Radioisotope Thermoelectric Generator) on the Ulysses Solar Exploration Mission

Potential radiation impacts from launch of the Ulysses solar exploration experiment were evaluated using eight postulated accident scenarios. Lifetime individual dose estimates rarely exceeded 1 mrem. Most of the potential health effects would come from inhalation exposures immediately after an accident, rather than from ingestion of contaminated food or water, or from inhalation of resuspended plutonium from contaminated ground. For local Florida accidents (that is, during the first minute after launch), an average source term accident was estimated to cause a total added cancer risk of up to 0.2 deaths. For accidents at later times after launch, a worldwide cancer risk of up to three cases was calculated (with a four in a million probability). Upper bound estimates were calculated to be about 10 times higher. 83 refs.
Date: November 2, 1990
Creator: Goldman, M. (California Univ., Davis, CA (USA)); Nelson, R.C. (EG and G Idaho, Inc., Idaho Falls, ID (USA)); Bollinger, L. (Air Force Inspection and Safety Center, Kirtland AFB, NM (USA)); Hoover, M.D. (Lovelace Biomedical and Environmental Research Inst., Albuquerque, NM (USA). Inhalation Toxicology Research Inst.); Templeton, W. (Pacific Northwest Lab., Richland, WA (USA)) & Anspaugh, L. (Lawren
System: The UNT Digital Library
SEM (Scanning Electron Microscopy) Analysis of Rock Varnish Chemistry for Cation-Ratio Dating: An Examination of Electron Beam Penetration Depths (open access)

SEM (Scanning Electron Microscopy) Analysis of Rock Varnish Chemistry for Cation-Ratio Dating: An Examination of Electron Beam Penetration Depths

Rock varnish is a microns-thick manganese- and iron-rich coating that forms on exposed rock surfaces in arid and semi-arid environments. Empirical correlations of the varnish cation ratio (K+Ca)/Ti with age have been used to estimate ages of geomorphic surfaces, with varnish chemistry generally acquired by either proton-induced x-ray emission (PIXE) analysis of natural varnish surfaces. Chemical analyses of rock varnish with SEM/EDX utilize a sequence of accelerating voltages to vary penetration depths into the sample. Using elemental x-ray maps of natural varnish surfaces with SEM/EDX, penetration into the substrate can be recognized at accelerating voltages where contamination with substrate is inferred from SEM/EDX chemical analyses. This demonstrates the ability of the SEM method to obtain varnish chemistry with minimal inclusion of substrate. Calculations of theoretical x-ray depth-distribution ({phi}({rho}z)) curves in varnish indicate that at an accelerating voltage of 10 kV most of the emitted electrons are generated in the upper 0.5 micron of a sample. At a higher voltage of 30 kV most of the signal is still restricted to the upper 2 microns, representing a very small percentage of total varnish volume in many cases. The ability of the SEM method to obtain empirical correlations of the chemistry of …
Date: April 2, 1990
Creator: Reneau, Steven L.; Raymond, Robert Jr.; Harrington, Charles D. & Hagan, Roland C.
System: The UNT Digital Library
The LLNL (Lawrence Livermore National Laboratory) ICF (Inertial Confinement Fusion) Program: Progress toward ignition in the Laboratory (open access)

The LLNL (Lawrence Livermore National Laboratory) ICF (Inertial Confinement Fusion) Program: Progress toward ignition in the Laboratory

The Inertial Confinement Fusion (ICF) Program at the Lawrence Livermore National Laboratory (LLNL) has made substantial progress in target physics, target diagnostics, and laser science and technology. In each area, progress required the development of experimental techniques and computational modeling. The objectives of the target physics experiments in the Nova laser facility are to address and understand critical physics issues that determine the conditions required to achieve ignition and gain in an ICF capsule. The LLNL experimental program primarily addresses indirect-drive implosions, in which the capsule is driven by x rays produced by the interaction of the laser light with a high-Z plasma. Experiments address both the physics of generating the radiation environment in a laser-driven hohlraum and the physics associated with imploding ICF capsules to ignition and high-gain conditions in the absence of alpha deposition. Recent experiments and modeling have established much of the physics necessary to validate the basic concept of ignition and ICF target gain in the laboratory. The rapid progress made in the past several years, and in particular, recent results showing higher radiation drive temperatures and implosion velocities than previously obtained and assumed for high-gain target designs, has led LLNL to propose an upgrade of …
Date: October 2, 1990
Creator: Storm, E.; Batha, S. H.; Bernat, T. P.; Bibeau, C.; Cable, M. D.; Caird, J. A. et al.
System: The UNT Digital Library
Marker evaluation of human breast and bladder cancers (open access)

Marker evaluation of human breast and bladder cancers

We are investigating multiple markers in human breast and bladder cancers. Our aim is to identify markers that are clinically relevant and that contribute to our understanding of the disease process in individual patients. Good markers accurately assess the malignant potential of a cancer in an individual patient. Thus, they help identify those cancers that will recur, and they may be used to predict more accurately time to recurrence, response to treatment, and overall prognosis. Therapy and patient management may then be optimized to the individual patient. Relevant markers reflect the underlying pathobiology of individual tumors. As a tissue undergoes transformation from benign to malignant, the cells lose their differentiated phenotype. As a generalization, the more the cellular phenotype, cellular proliferation and cellular genotype depart from normal, the more advanced is the tumor in its biological evolution and the more likely it is that the patient has a poor prognosis. We use three studies to illustrate our investigation of potential tumor markers. Breast cancers are labeled in vivo with 5-bromodeoxyuridine (BrdUrd) to give a direct measure of the tumor labeling index. Bladder cancers are analyzed immunocytochemically using an antibody against proliferation. Finally, the techniques of molecular genetics are used to …
Date: November 2, 1990
Creator: Mayall, B. H.; Carroll, P. R.; Chen, Ling-Chun; Cohen, M. B.; Goodson III, W. H.; Smith, H. S. et al.
System: The UNT Digital Library
Limits on the masses of supersymmetric particles from 1. 8 TeV p p collisions (open access)

Limits on the masses of supersymmetric particles from 1. 8 TeV p p collisions

Preliminary analysis of p{bar p} collision events at {radical}s = 1.8 TeV using events with large missing transverse energy and on two (four) jets in a minimal SUSY model places new limits on the masses of squarks (gluinos). The data sample (4 pb{sup {minus}1}) was taken in 1988--89 and is approximately 160 times as large as the data sample from our earlier 1987 run (25 nb{sup {minus}1}). 5 refs., 1 fig.
Date: October 2, 1990
Creator: Beretvas, A.
System: The UNT Digital Library
A summary of the results from LASS (Large Aperture Superconducting Solenoid) and the future of strange quake spectroscopy (open access)

A summary of the results from LASS (Large Aperture Superconducting Solenoid) and the future of strange quake spectroscopy

A brief summary is presented of results pertinent to quark spectroscopy derived from high statistics data on K{sup {minus}}p interactions obtained with the LASS spectrometer at SLAC. The present status of strange meson spectroscopy is briefly reviewed, and the impact of the proposed KAON Factory on the future of the subject considered. 36 refs., 24 figs.
Date: May 2, 1990
Creator: Aston, D.; Bienz, T.; Bird, T.; Dunwoodie, W.; Johnson, W.; Kunz, P. et al.
System: The UNT Digital Library
[The Dallas Voice: Gay voters find friends and enemies on ballot] (open access)

[The Dallas Voice: Gay voters find friends and enemies on ballot]

The Dallas Voice featuring an article about LGBT friendly candidates and a campaign ad for Ann Richards.
Date: November 2, 1990
Creator: unknown
System: The UNT Digital Library
Damage measurements on optical materials for use in high-peak-power lasers (open access)

Damage measurements on optical materials for use in high-peak-power lasers

Recently, we have expanded our efforts to develop state-of-the-art optical components for use in large-scale, high-peak-power, solid state lasers. Laser-induced damage to many of these components sets critical constraints on construction costs and limits the peak powers attainable in current and proposed devices. Increasing the damage threshold whenever possible by improving materials fabrication technology is therefore the ultimate goal of our work. Our research has resulted in an extensive database of laser-damage measurements. We present summaries of these measurements with particular emphasis on those taken at 1064 nm and 355 nm.
Date: May 2, 1990
Creator: Rainer, F.; Brusasco, R. M.; Campbell, J. H.; DeMarco, F. P.; Gonzales, R. P.; Kozlowski, M. R. et al.
System: The UNT Digital Library
Secondary interactions in HIJET (open access)

Secondary interactions in HIJET

This talk deals with the investigation of secondary interactions in proton-nucleus and nucleus-nucleus collisions using the Monte Carlo event generator HIJET.
Date: April 2, 1990
Creator: Longacre, R. S.
System: The UNT Digital Library
Nucleosynthesis in a baryon-inhomogeneous universe with coupled baryon diffusion (open access)

Nucleosynthesis in a baryon-inhomogeneous universe with coupled baryon diffusion

Detailed calculations of big-bang nucleosynthesis in baryon-inhomogeneous universes show that {Omega}{sub b} can be considerably larger than its limit from standard big-bang nucleosynthesis. Such results require that late-time hydrodynamic effects deplete overproduction of {sup 7}Li and that the QCD surface tension be near the cube of the QCD coexistence temperature for fluctuations of the correct length scales to arise. 15 refs., 1 fig.
Date: August 2, 1990
Creator: Meyer, B.S.
System: The UNT Digital Library