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Cancer Risk Assessment: Should New Science be Applied? Workgroup summary (open access)

Cancer Risk Assessment: Should New Science be Applied? Workgroup summary

OAK-B135 A symposium discussing the implications of certain phenomena observed in radiation biology for cancer risk assessment in general. In July of 2002 a workshop was convened that explored some of the intercellular phenomena that appear to condition responses to carcinogen exposure. Effects that result from communication between cells that appear to either increase the sphere of damage or to modify the sensitivity of cells to further damage were of particular interest. Much of the discussion focused on the effects of ionizing radiation that were transmitted from cells directly hit to cells not receiving direct exposure to radiation (bystander cells). In cell culture, increased rates of mutation, chromosomal aberration, apoptosis, genomic instability, and decreased clonogenic survival have all been observed in cells that have experienced no direct radiation. In addition, there is evidence that low doses of radiation or certain chemicals give rise to adaptive responses in which the treated cells develop resistance to the effects of high doses given in subsequent exposures. Data were presented at the workshop indicating that low dose exposure of animals to radiation and some chemicals frequently reduces the spontaneous rate of mutation in vitro and tumor responses in vivo. Finally, it was concluded that …
Date: December 15, 2002
Creator: Bull, Richard J. & Brooks, Antone L.
System: The UNT Digital Library
Amplitude Control of Solid-State Modulators for Precision Fast Kicker Applications (open access)

Amplitude Control of Solid-State Modulators for Precision Fast Kicker Applications

A solid-state modulator with very fast rise and fall times, pulse width agility, and multi-pulse burst and intra-pulse amplitude adjustment capability for use with high speed electron beam kickers has been designed and tested at LLNL. The modulator uses multiple solid-state modules stacked in an inductive-adder configuration. Amplitude adjustment is provided by controlling individual modules in the adder, and is used to compensate for transverse e-beam motion as well as the dynamic response and beam-induced steering effects associated with the kicker structure. A control algorithm calculates a voltage based on measured e-beam displacement and adjusts the modulator to regulate beam centroid position. This paper presents design details of amplitude control along with measured performance data from kicker operation on the ETA-II accelerator at LLNL.
Date: November 15, 2002
Creator: Watson, J. A.; Anaya, R. M.; Caporaso, G. C.; Chen, Y. J.; Cook, E. G.; Lee, B. S. et al.
System: The UNT Digital Library
How the Grid will affect the architecture of future visualization systems (open access)

How the Grid will affect the architecture of future visualization systems

None
Date: November 15, 2002
Creator: Shalf, John & Bethel, E. Wes
System: The UNT Digital Library
Identification and Elimination of Fluorescent Surface-Damage Precursors on DKDP Optics (open access)

Identification and Elimination of Fluorescent Surface-Damage Precursors on DKDP Optics

Fluorescing surface defects that led to damage upon 351-nm laser exposure below 7 J/cm{sup 2} (3-11s) in DKDP optics were reported in these proceedings by this group a year ago. Subsequent laser damage experiments have correlated the density of these damage precursors to single-point diamond finishing conditions. Every diamond-finishing schedule contains brittle-mode cutting and ductile-mode cutting in a taper-down sequence. Finishing experiments have traced the occurrence of these defects to insufficient ductile-mode removal of subsurface damage incurred during prior brittle-mode cutting. Additionally, a correlation between defect fluorescence, laser-induced damage, and defect morphology has been established. Laser-induced damage tests also suggest a correlation between growth method and damage probability. Current experiments indicate that damage-prone defects can be minimized with the proper choice of diamond finishing conditions.
Date: November 15, 2002
Creator: Nostrand, M. C.; Thompson, S.; Siekhaus, W.; Fluss, M.; Hahn, D.; Whitman, P. et al.
System: The UNT Digital Library
IFE Chamber Technology - Status and Future Challenges (open access)

IFE Chamber Technology - Status and Future Challenges

Significant progress has been made on addressing critical issues for inertial fusion energy (IFE) chambers for heavy-ion, laser and Z-pinch drivers. A variety of chamber concepts are being investigated including dry-wall (currently favored for laser IFE), wetted-wall (applicable to both laser and ion drivers), and thick-liquid-wall favored by heavy ion and z-pinch drivers. Recent progress and remaining challenges in developing IFE chambers are reviewed.
Date: November 15, 2002
Creator: Meier, W. R.; Raffrary, A. R.; Abdel-Khalik, S.; Kulcinski, G.; Latkowski, J. F.; Najmabadi, F. et al.
System: The UNT Digital Library
Magnetic Field Induced Phase Transitions in Gd5(Si1.95Ge2.05) Single Crystal and the Anisotropic Magnetocaloric Effect (open access)

Magnetic Field Induced Phase Transitions in Gd5(Si1.95Ge2.05) Single Crystal and the Anisotropic Magnetocaloric Effect

None
Date: November 15, 2002
Creator: Tang, H.; Pecharsky, V. K.; Pecharsky, A. O.; Schlagel, D. L.; Lograsso, T. A. & Gschneidner, K. A.
System: The UNT Digital Library
Modeling AFM Induced Mechanical Deformation of Living Cells (open access)

Modeling AFM Induced Mechanical Deformation of Living Cells

Finite element modeling has been applied to study deformation of living cells in Atomic Force Microscopy (AFM) and particularly Recognition Force Microscopy (RFM). The abstract mechanical problem of interest is the response to RFM point loads of an incompressible medium enclosed in a fluid membrane. Cells are soft systems, susceptible to large deformations in the course of an RFM measurement. Often the local properties such as receptor anchoring forces, the reason for the measurement, are obscured by the response of the cell as a whole. Modeling can deconvolute these effects. This facilitates experimental efforts to have reproducible measurements of mechanical and chemical properties at specific kinds of receptor sites on the membrane of a living cell. In this article we briefly review the RFM technique for cells and the problems it poses, and then report on recent progress in modeling the deformation of cells by a point load.
Date: November 15, 2002
Creator: Rudd, Robert E.; McElfresh, Michael; Balhorn, Rod; Allen, Michael J. & Belak, James
System: The UNT Digital Library
Review of Corrosion Modes for Alloy 22 Regarding Lifetime Expectancy of Nuclear Waste Containers (open access)

Review of Corrosion Modes for Alloy 22 Regarding Lifetime Expectancy of Nuclear Waste Containers

Alloy 22 (UNS N06022) was selected to fabricate the corrosion resistant outer barrier of a two-layer waste package container for nuclear waste at the designated repository site in Yucca Mountain in Nevada (USA). A testing program is underway to characterize and quantify three main modes of corrosion that may occur at the site. Current results show that the containers would perform well under general corrosion, localized corrosion and environmentally assisted cracking (EAC). For example, the general corrosion rate is expected to be below 100 nm/year and the container is predicted to be outside the range of potential for localized corrosion and environmentally assisted cracking.
Date: November 15, 2002
Creator: Rebak, R. B. & Estill, J. C.
System: The UNT Digital Library
Capillary rise in nesting cylinders (open access)

Capillary rise in nesting cylinders

None
Date: October 15, 2002
Creator: Brady, Victor; Concus, Paul & Finn, Robert
System: The UNT Digital Library
Comparison of AlxGa1-xN films grown on sapphire by MBE underN-rich and Ga-rich conditions (open access)

Comparison of AlxGa1-xN films grown on sapphire by MBE underN-rich and Ga-rich conditions

Al{sub x}Ga{sub 1-x}N layers grown under N-rich and Ga-rich conditions were investigated using transmission electron microscopy (TEM) and photoluminescence (PL). Despite a high density of threading dislocations ({approx}10{sup 10} cm{sup -2}) these layers had high PL quantum efficiencies. Both, TEM and PL studies showed significant differences between layers grown under N- and Ga-rich conditions. The results indicate that edge dislocations do contribute to nonradiative recombination in Al{sub x}Ga{sub 1-x}N layers.
Date: October 15, 2002
Creator: Jasinski, J.; Liliental-Weber, Z.; He, L.; Reshchikov, M.A. & Morkoc, H.
System: The UNT Digital Library
Large Space Telescopes Using Fresnel Lens for Power Beaming, Astronomy and Sail Missions (open access)

Large Space Telescopes Using Fresnel Lens for Power Beaming, Astronomy and Sail Missions

The concept of using Fresnel optics as part of power beaming, astronomy or sail systems has been suggested by several authors. The primary issues for large Fresnel optics are the difficulties in fabricating these structures and deploying them in space and for astronomy missions the extremely narrow frequency range of these optics. In proposals where the telescope is used to transmit narrow frequency laser power, the narrow bandwidth has not been an issue. In applications where the optic is to be used as part of a telescope, only around 10{sup -5} to limited frequency response of a Fresnel optic is addressed by the use of a corrective optic that will broaden the frequency response of the telescope by three or four orders of magnitude. This broadening will dramatically increase the optical power capabilities of the system and will allow some spectroscopy studies over a limited range. Both the fabrication of Fresnel optics as large as five meters and the use of corrector optics for telescopes have been demonstrated at LLNL. For solar and laser sail missions the use of Fresnel amplitude zone plates made of very thin sail material is also discussed.
Date: October 15, 2002
Creator: Early, J T
System: The UNT Digital Library
Apolipoprotein A5: A newly identified gene impacting plasmatriglyceride levels in humans and mice (open access)

Apolipoprotein A5: A newly identified gene impacting plasmatriglyceride levels in humans and mice

Apolipoprotein A5 (APOA5) is a newly described member of theapolipoprotein gene family whose initial discovery arose from comparativesequence analysis of the mammalian APOA1/C3/A4 gene cluster. Functionalstudies in mice indicated that alteration in the level of APOA5significantly impacted plasma triglyceride concentrations. Miceover-expressing human APOA5 displayed significantly reducedtriglycerides, while mice lacking apoA5 had a large increase in thislipid parameter. Studies in humans have also suggested an important rolefor APOA5 in determining plasma triglyceride concentrations. In theseexperiments, polymorphisms in the human gene were found to define severalcommon haplotypes that were associated with significant changes intriglyceride concentrations in multiple populations. Several separateclinical studies have provided consistent and strong support for theeffect with 24 percent of Caucasians, 35 percent of African-Americans and53 percent of Hispanics carrying APOA5 haplotypes associated withincreased plasma triglyceride levels. In summary, APOA5 represents anewly discovered gene involved in triglyceride metabolism in both humansand mice whose mechanism of action remains to be deciphered.
Date: September 15, 2002
Creator: Pennacchio, Len A. & Rubin, Edward M.
System: The UNT Digital Library
Linkage and association of haplotypes at the APOA1/C3/A4/A5 genecluster to familial combined hyperlipidemia (open access)

Linkage and association of haplotypes at the APOA1/C3/A4/A5 genecluster to familial combined hyperlipidemia

Combined hyperlipidemia (CHL) is a common disorder of lipidmetabolism that leads to an increased risk of cardiovascular disease. Thelipid profile of CHL is characterised by high levels of atherogeniclipoproteins and low levels of high-density-lipoprotein-cholesterol.Apolipoprotein (APO) A5 is a newly discovered gene involved in lipidmetabolism located within 30kbp of the APOA1/C3/A4 gene cluster. Previousstudies have indicated that sequence variants in this cluster areassociated with increased plasma lipid levels. To establish whethervariation at the APOA5 gene contributes to the transmission of CHL, weperformed linkage and linkage disequilibrium (LD) tests on a large cohortof families (n=128) with familial CHL (FCHL). The linkage data producedevidence for linkage of the APOA1/C3/A4/A5 genomic interval to FCHL (NPL= 1.7, P = 0.042). The LD studies substantiated these data. Twoindependent rare alleles, APOA5c.56G and APOC3c.386G of this gene clusterwere over-transmitted in FCHL (P = 0.004 and 0.007, respectively), andthis was associated with a reduced transmission of the most commonAPOA1/C3/A4/A5 haplotype (frequency 0.4425) to affected subjects (P =0.013). The APOA5c.56G allele was associated with increased plasmatriglyceride levels in FCHL probands, whereas the second, andindependent, APOC3c.386G allele was associated with increased plasmatriglyceride levels in FCHL pedigree founders. Thus, this allele (or anallele in LD) may mark a quantitative trait associated …
Date: September 15, 2002
Creator: Eichenbaum-Voline, Sophie; Olivier, Michael; Jones, Emma L.; Naoumova, Rossitza P.; Jones, Bethan; Gau, Brian et al.
System: The UNT Digital Library
Microbial Transformations of Uranium Complexed With Organic and Inorganic Ligands. (open access)

Microbial Transformations of Uranium Complexed With Organic and Inorganic Ligands.

Biotransformation of various chemical forms of uranium present in wastes, contaminated soils and materials by microorganisms under different process conditions such as aerobic and anaerobic (denitrifying, iron-reducing, fermentative, and sulfate-reducing) conditions will affect the solubility, bioavailability, and mobility of uranium in the natural environment. Fundamental understanding of the mechanisms of microbial transformations of uranium under a variety of environmental conditions will be useful in developing appropriate remediation and waste management strategies as well as predicting the microbial impacts on the long-term stewardship of contaminated sites.
Date: September 15, 2002
Creator: Francis, A. J.
System: The UNT Digital Library
Progress in the study of mesh refinement for particle-in-cell plasma simulations and its application to heavy ion fusion (open access)

Progress in the study of mesh refinement for particle-in-cell plasma simulations and its application to heavy ion fusion

The numerical simulation of the driving beams in a heavy ion fusion power plant is a challenging task, and, despite rapid progress in computer power, one must consider the use of the most advanced numerical techniques. One of the difficulties of these simulations resides in the disparity of scales in time and in space which must be resolved. When these disparities are in distinctive zones of the simulation region, a method which has proven to be effective in other areas (e.g. fluid dynamics simulations) is the Adaptive-Mesh-Refinement (AMR) technique. We follow in this article the progress accomplished in the last few months in the merging of the AMR technique with Particle-In-Cell (PIC) method. This includes a detailed modeling of the Lampel-Tiefenback solution for the one-dimensional diode using novel techniques to suppress undesirable numerical oscillations and an AMR patch to follow the head of the particle distribution. We also report new results concerning the modeling of ion sources using the axisymmetric WARPRZ-AMR prototype showing the utility of an AMR patch resolving the emitter vicinity and the beam edge.
Date: September 15, 2002
Creator: Vay, J. L.; Friedman, A. & Grote, D. P.
System: The UNT Digital Library
Updating the Nrc Guidance for Human Factors Engineering Reviews. (open access)

Updating the Nrc Guidance for Human Factors Engineering Reviews.

None
Date: September 15, 2002
Creator: O Hara, J. M.; Brown, W. S.; Higgins, J. C.; Persensky, J. J.; Lewis, P. M. & Bongarra, J.
System: The UNT Digital Library
Updating the Nrc Guidance for Human Factors Engineering Reviews. (open access)

Updating the Nrc Guidance for Human Factors Engineering Reviews.

The U.S. Nuclear Regulatory Commission (NRC) reviews the human factors engineering (HFE) aspects of nuclear plants. NUREG-0800 (Standard Review Plan), Chapter 18, ''Human Factors Engineering,'' is the principal NRC staff guidance document. Two main documents provide the review criteria to support the evaluations. The HFE Program Review Model (NUREG-0711) addresses the design process from planning to verification and validation to design implementation. The Human-System Interface Design Review Guidelines (NUREG-0700) provides the guidelines for the review of the HFE aspects of human-system interface technology, such as alarms, information systems, controls, and control room design. Since these documents were published in 1994 and 1996 respectively, they have been used by NRC staff, contractors, nuclear industry organizations, as well as by numerous organizations outside the nuclear industry. Using feedback from users and NRC research conducted in recent years, both documents have been revised and updated. This was done to ensure that they remain state-of-the-art evaluation tools for changing nuclear industry issues and emerging technologies. This paper describes the methodology used to revise and update the documents and summarizes the changes made to each and their current contents. Index Terms for this report are: Control system human factors, Ergonomics, Human factors, Nuclear power generation …
Date: September 15, 2002
Creator: O Hara, J. M.; Brown, W. S.; Higgins, J. C.; Persensky, J. J.; Lewis, P. M. & Bongarra, J.
System: The UNT Digital Library
Designing a flexible grid enabled scientific modeling interface. (open access)

Designing a flexible grid enabled scientific modeling interface.

The Espresso Scientific Modeling Interface (Espresso) is a scientific modeling productivity tool developed from climate modelers. Espresso was designed to be an extensible interface to both scientific models and Grid resources. It also aims to be a contemporary piece of software that relies on Globus.org's Java CoG Kit for a Grid toolkit, Sun's Java 2 API and is configured using XML. This article covers the design implementation of Espresso's Grid functionality and how it interacts with existing scientific models. The authors give specific examples of how they have designed Espresso to perform climate simulations using the PSU/NCAR MM5 atmospheric model. Plans to incorporate the CCSM and FOAM climate models are also discussed.
Date: August 15, 2002
Creator: Dvorak, M.; Taylor, J. & Mickelson, S.
System: The UNT Digital Library
Developing Grid based infrastructure or climate modeling (open access)

Developing Grid based infrastructure or climate modeling

In this paper we discuss the development of a high performance climate modeling system as an example of the application of Grid based technology to climate modeling. The climate simulation system at Argonne currently includes a scientific modeling interface (Espresso) written in Java which incorporates Globus middleware to facilitate climate simulations on the Grid. The climate modeling system also includes a high performance version of MM5v3.4 modified for long climate simulations on our 512 processor Linux cluster (Chiba City), an interactive web based tool to facilitate analysis and collaboration via the web, and an enhanced version of the Cave5D software capable of visualizing large climate data sets. We plan to incorporate other climate modeling systems such as the Fast Ocean Atmosphere Model (FOAM) and the National Center for Atmospheric Research's (NCAR) Community Climate Systems Model (CCSM) within Espresso to facilitate their application on computational grids.
Date: August 15, 2002
Creator: Taylor, J.; Dvorak, M. & Mickelson, S.
System: The UNT Digital Library
Characterization of upper troposphere water vapor measurements during AFWEX using LASE. (open access)

Characterization of upper troposphere water vapor measurements during AFWEX using LASE.

Water vapor profiles from NASA's Lidar Atmospheric Sensing Experiment (LASE) system acquired during the ARM/FIRE Water Vapor Experiment (AFWEX) are used to characterize upper troposphere (UT) water vapor measured by ground-based Raman lidars, radiosondes, and in situ aircraft sensors. Initial comparisons showed the average Vaisala radiosonde measurements to be 5-15% drier than the average LASE, Raman lidar, and DC-8 in situ diode laser hygrometer measurements. They show that corrections to the Raman lidar and Vaisala measurements significantly reduce these differences. Precipitable water vapor (PWV) derived from the LASE water vapor profiles agrees within 3% on average with PWV derived from the ARM ground-based microwave radiometer (MWR). The agreement among the LASE, Raman lidar, and MWR measurements demonstrates how the LASE measurements can be used to characterize both profile and column water vapor measurements and that ARM Raman lidar, when calibrated using the MWR PWV, can provide accurate UT water vapor measurements.
Date: July 15, 2002
Creator: Ferrare, R. A.; Browell, E. V.; Ismail, I.; Kooi, S.; Brasseur, L. H.; Brackett, V. G. et al.
System: The UNT Digital Library
Downstream System for the Second Axis of the DARHT Facility (open access)

Downstream System for the Second Axis of the DARHT Facility

This paper presents the physics design of the DARHT-II downstream system, which consists of a diagnostic beam stop, a fast, high-precision kicker system and the x-ray converter target assembly. The beamline configuration, the transverse resistive wall instability and the ion hose instability modeling are presented. They also discuss elimination of spot size dilution during kicker switching and implementation of the foil-barrier scheme to minimize the backstreaming ion focusing effects. Finally, they present the target converter's configuration, and the simulated DARHT-II x-ray spot sizes and doses. Some experimental results, which support the physics design, are also presented.
Date: July 15, 2002
Creator: Chen, Y. J.; Bertolini, L.; Caporaso, G. J.; Chambers, F. W.; Cook, E. G.; Falabella, S. et al.
System: The UNT Digital Library
Fernald restoration: ecologists and engineers integrate restoration and cleanup (open access)

Fernald restoration: ecologists and engineers integrate restoration and cleanup

As cleanup workers excavate pits and tear down buildings at the Fernald site in southwest Ohio, site ecologists are working side-by-side to create thriving wetlands and develop the early stages of forest, prairie, and savanna ecosystems to restore natural resources that were impacted by years of site operations. In 1998, the U.S. Department of Energy-Fernald Office (DOE-FN) and its cleanup contractor, Fluor Fernald, Inc., initiated several ecological restoration projects in perimeter areas of the site (e.g., areas not used for or impacted by uranium processing or waste management). The projects are part of Fernald's final land use plan to restore natural resources over 904 acres of the 1,050-acre site. Pete Yerace, the DOE-FN Natural Resource Trustee representative is working with the Fernald Natural Resource Trustees in an oversight role to resolve the state of Ohio's 1986 claim against DOE for injuries to natural resources. Fluor Fernald, Inc., and DOE-FN developed the ''Natural Resource Restoration Plan'', which outlines 15 major restoration projects for the site and will restore injured natural resources at the site. In general, Fernald's plan includes grading to maximize the formation of wetlands or expanded floodplain, amending soil where topsoil has been removed during excavation, and establishing native …
Date: July 15, 2002
Creator: Woods, Eric & Homer, John
System: The UNT Digital Library
Portable Multiplex Pathogen Detector (open access)

Portable Multiplex Pathogen Detector

Tumor marker concentrations in serum provide useful information regarding clinical stage and prognosis of cancer and can thus be used for presymptomatic diagnostic purposes. Currently, detection and identification of soluble analytes in biological fluids is conducted by methods including bioassays, ELISA, PCR, DNA chip or strip tests. While these technologies are generally sensitive and specific, they are time consuming, labor intensive and cannot be multiplexed. Our goal is to develop a simple, point-of-care, portable, liquid array-based immunoassay device capable of simultaneous detection of a variety of cancer markers. Here we describe the development of assays for the detection of Serum Prostate Specific Antigen, and Ovalbumin from a single sample. The multiplexed immunoassays utilize polystyrene microbeads. The beads are imbedded with precise ratios of red and orange fluorescent dyes yielding an array of 100 beads, each with a unique spectral address (Figure 1). Each bead can be coated with capture antibodies specific for a given antigen. After antigen capture, secondary antibodies sandwich the bound antigen and are indirectly labeled by the fluorescent reporter phycoerythrin (PE). Each optically encoded and fluorescently-labeled microbead is then individually interrogated. A red laser excites the dye molecules imbedded inside the bead and classifies the bead to …
Date: July 15, 2002
Creator: Visuri, S; McBride, M T; Matthews, D & Rao, R
System: The UNT Digital Library
Advanced intraundulator electron beam diagnostics using COTR techniques. (open access)

Advanced intraundulator electron beam diagnostics using COTR techniques.

None
Date: May 15, 2002
Creator: Lumpkin, A. H. L.; Berg, W. J. B.; Biedron, S. B.; Borland, M. B.; Chae, Y. C. C.; Dejus, R. D. et al.
System: The UNT Digital Library