Geometrically induced metastability and holography (open access)

Geometrically induced metastability and holography

We construct metastable configurations of branes and anti-branes wrapping 2-spheres inside local Calabi-Yau manifolds and study their large N duals. These duals are Calabi-Yau manifolds in which the wrapped 2-spheres have been replaced by 3-spheres with flux through them, and supersymmetry is spontaneously broken. The geometry of the non-supersymmetric vacuum is exactly calculable to all orders of the't Hooft parameter, and to the leading order in 1/N. The computation utilizes the same matrix model techniques that were used in the supersymmetric context. This provides a novel mechanism for breaking supersymmetry in the context of flux compactifications.
Date: October 23, 2006
Creator: Aganagic, Mina; Aganagic, Mina; Beem, Christopher; Seo, Jihye & Vafa, Cumrun
Object Type: Article
System: The UNT Digital Library
Final technical report for Interagency Agreement No. DE-AI02-98ER62683: Development of a functional genomics approach to use radiation-induced changes in gene expression to monitor for low dose and low dose-rate exposures (open access)

Final technical report for Interagency Agreement No. DE-AI02-98ER62683: Development of a functional genomics approach to use radiation-induced changes in gene expression to monitor for low dose and low dose-rate exposures

Microarray analysis and other molecular biology techniques were used to investigate the regulation of gene expression following ionizing radiation exposure.
Date: October 23, 2001
Creator: Albert J. Fornace, Jr.
Object Type: Report
System: The UNT Digital Library
Postranslational Modifications of P53: Upstream Signaling Pathways. (open access)

Postranslational Modifications of P53: Upstream Signaling Pathways.

The p53 tumor suppressor is a tetrameric transcription factor that is posttranslational modified at >20 different sites by phosphorylation, acetylation, or sumoylation in response to various cellular stress conditions. Specific posttranslational modifications, or groups of modifications, that result from the activation of different stress-induced signaling pathways are thought to modulate p53 activity to regulate cell fate by inducing cell cycle arrest, apoptosis, or cellular senescence. Here we review recent progress in characterizing the upstream signaling pathways whose activation in response to various genotoxic and non-genotoxic stresses result in p53 posttranslational modifications.
Date: October 23, 2003
Creator: Anderson, C. W. & Appella, E.
Object Type: Report
System: The UNT Digital Library
MINOR PARAMETERS NEEDED FOR INDIVIDUAL-DOSE CALCULATIONS: Final Report for Tasks 7.1, 7.2, 8.1, 8.2, 9.1, 9.2, and 9.3 (open access)

MINOR PARAMETERS NEEDED FOR INDIVIDUAL-DOSE CALCULATIONS: Final Report for Tasks 7.1, 7.2, 8.1, 8.2, 9.1, 9.2, and 9.3

This brief report documents the selection of parameters needed to support individual-dose calculations from 131I released into the environment with gaseous effluents from the Mayak Production Association.
Date: October 23, 2009
Creator: Anspaugh, L. R. & Napier, Bruce A.
Object Type: Report
System: The UNT Digital Library
RESRAD connection for facilitating MARSSIM analysis : an illustration of applying the OpenLink concept. (open access)

RESRAD connection for facilitating MARSSIM analysis : an illustration of applying the OpenLink concept.

The focus of this work is to more tightly integrate tools traditionally used in MARSSIM (Multi-Agency Radiation Survey and Site Investigation Manual) final status survey design. MARSSIM provides guidance on appropriate methodologies for establishing that dose or risk-based standards for a site contaminated with radionuclides have been achieved. RESidual RADioactive (RESRAD) codes are used by the U.S. Department of Energy, the U.S. Nuclear Regulatory Commission, and other federal agencies to convert dose-based cleanup criteria to site-specific-derived concentration guideline level (DCGL) requirements. By implementing MARSSIM concepts directly within RESRAD, users can now directly generate site-specific DCGL requirements and associated area factors.
Date: October 23, 2002
Creator: Arnish, J.; Chen, S. Y.; Johnson, R.; LePoire, D.; Klett, T. & Yu, C.
Object Type: Report
System: The UNT Digital Library
Building America Best Practices Series, Volume 9: Builders Challenge Guide to 40% Whole-House Energy Savings in the Hot-Dry and Mixed-Dry Climates (open access)

Building America Best Practices Series, Volume 9: Builders Challenge Guide to 40% Whole-House Energy Savings in the Hot-Dry and Mixed-Dry Climates

This best practices guide is the ninth in a series of guides for builders produced by the U.S. Department of Energy’s Building America Program. This guide book is a resource to help builders design and construct homes that are among the most energy-efficient available, while addressing issues such as building durability, indoor air quality, and occupant health, safety, and comfort. With the measures described in this guide, builders in the hot-dry and mixed-dry climates can achieve homes that have whole house energy savings of 40% over the Building America benchmark (a home built to mid-1990s building practices roughly equivalent to the 1993 Model Energy Code) with no added overall costs for consumers. These best practices are based on the results of research and demonstration projects conducted by Building America’s research teams. The guide includes information for managers, designers, marketers, site supervisors, and subcontractors, as well as case studies of builders who are successfully building homes that cut energy use by 40% in the hot-dry and mixed-dry climates.
Date: October 23, 2009
Creator: Baechler, Michael C.; Gilbride, Theresa L.; Hefty, Marye G.; Williamson, Jennifer L.; Ruiz, Kathleen A.; Bartlett, Rosemarie et al.
Object Type: Report
System: The UNT Digital Library
Performance of a phase-conjugate-engine implementing a finite-bit phase correction (open access)

Performance of a phase-conjugate-engine implementing a finite-bit phase correction

This article examines the achievable Strehl ratio when a finite-bit correction to an aberrated wave-front is implemented. The phase-conjugate-engine (PCE) used to measure the aberrated wavefront consists of a quadrature interferometric wave-front sensor, a liquid-crystal spatial-light-modulator and computer hardware/software to calculate and apply the correction. A finite-bit approximation to the conjugate phase is calculated and applied to the spatial light modulator to remove the aberrations from the optical beam. The experimentally determined Strehl ratio of the corrected beam is compared with analytical expressions for the expected Strehl ratio and shown to be in good agreement with those predictions.
Date: October 23, 2003
Creator: Baker, K.; Stappaerts, E.; Wilks, S.; Young, P.; Gavel, D.; Tucker, J. et al.
Object Type: Article
System: The UNT Digital Library
Determination of Parts-Per-Million Cesium in Simulated Nuclear Waste with the Cesium-Selective Electrode (open access)

Determination of Parts-Per-Million Cesium in Simulated Nuclear Waste with the Cesium-Selective Electrode

Because the molybdophosphate electrode was not sufficiently sensitive, and the reliability of the ''liquid state'' electrode for routine analysis was uncertain, a cesium-selective electrode of the proven liquid membrane type was developed. This paper describes preparation and testing of a liquid membrane electrode that contains cesium tetraphenylboron dissolved in 4-ethylnitrobenzene.
Date: October 23, 2001
Creator: Baumann, E. W.
Object Type: Article
System: The UNT Digital Library
Midwest Superconductivity Consortium - Final Progress Report October 2001 (open access)

Midwest Superconductivity Consortium - Final Progress Report October 2001

The basic mission of the Consortium was to advance the science and understanding of high-T{sub c} superconductivity and to promote the development of new materials and improved processing technology. Focused group efforts were the key element of the research program. One program area is the understanding of the layered structures involved in candidate materials and the factors that control their formation, stability and relationship superconductor properties. The other program area had a focus upon factors that limit or control the transport properties such as weak links, flux lattice behavior, and interfaces. Interactions among Consortium d with industrial armiates were an integral part of the program.
Date: October 23, 2001
Creator: Bement, Arden L.
Object Type: Report
System: The UNT Digital Library
The distribution and contaminant exposure of Rafinesque's Big-Eared Bats in South Carolina with an emphasis on bridge surveys. (open access)

The distribution and contaminant exposure of Rafinesque's Big-Eared Bats in South Carolina with an emphasis on bridge surveys.

Rafinesque's big-eared bat (Corynorhinus rafinesquii), an insectivorous mammal indigenous to the southern United States, has long been referred to as one of the least known bats in North America. Although there has been a moderate increase in the number of peer-reviewed articles published on this species in the past 6 years, the basic ecology and status of Rafinesque's big-eared bat remains largely obscure. Prior to 1996, when the United States Fish and Wildlife Service (USFWS) discontinued the list of Candidate Species, Rafinesque's big-eared bat was listed as a Federal Category 2 Candidate species. Currently, Rafinesque's big-eared bat is recognized as a ''species of special concern'' across most of its range but receives no legal protection. Nonetheless, the USFWS and numerous state agencies remain concerned about this species. Further biological research and field study are needed to resolve the conservation status of this taxona. In response to the paucity of information regarding the status and distribution of Rafinesque's big-eared bat, statewide survey of highway bridges used as roost sites was conducted.
Date: October 23, 2003
Creator: Bennett, F.M.; Loeb, S.C. & Bowerman, W.W.
Object Type: Report
System: The UNT Digital Library
Genus Oblivious Cross Parameterization: Robust Topological Management of Inter-surface Maps (open access)

Genus Oblivious Cross Parameterization: Robust Topological Management of Inter-surface Maps

We consider the problem of generating a map between two triangulated meshes, M and M{prime}, with arbitrary and possibly differing genus. This problem has rarely been tackled in its generality. Early schemes considered only topological spheres. Recent algorithms allow inputs with an arbitrary number of tunnels but require M and M{prime} to have equal genus, mapping tunnel to tunnel. Other schemes which allow more general inputs are not guaranteed to work and the authors do not provide a characterization of the input meshes that can be processed successfully. Moreover, the techniques have difficulty dealing with coarse meshes with many tunnels. In this paper we present the first robust approach to build a map between two meshes of arbitrary unequal genus. We also provide a simplified method for setting the initial alignment between M and M{prime}, reducing reliance on landmarks and allowing the user to select 'landmark tunnels' in addition to the standard landmark vertices. After computing the map, we automatically derive a continuous deformation from M to M{prime} using a variational implicit approach to describe the evolution of non-landmark tunnels. Overall, we achieve a cross parameterization scheme that is provably robust in the sense that it can map M to …
Date: October 23, 2007
Creator: Bennett, J C; Pascucci, V & Joy, K I
Object Type: Article
System: The UNT Digital Library
GEO-SEQ Best Practices Manual. Geologic Carbon Dioxide Sequestration: Site Evaluation to Implementation (open access)

GEO-SEQ Best Practices Manual. Geologic Carbon Dioxide Sequestration: Site Evaluation to Implementation

The first phase of the GEO-SEQ project was a multidisciplinary effort focused on investigating ways to lower the cost and risk of geologic carbon sequestration. Through our research in the GEO-SEQ project, we have produced results that may be of interest to the wider geologic carbon sequestration community. However, much of the knowledge developed in GEO-SEQ is not easily accessible because it is dispersed in the peer-reviewed literature and conference proceedings in individual papers on specific topics. The purpose of this report is to present key GEO-SEQ findings relevant to the practical implementation of geologic carbon sequestration in the form of a Best Practices Manual. Because our work in GEO-SEQ focused on the characterization and project development aspects, the scope of this report covers practices prior to injection, referred to as the design phase. The design phase encompasses activities such as selecting sites for which enhanced recovery may be possible, evaluating CO{sub 2} capacity and sequestration feasibility, and designing and evaluating monitoring approaches. Through this Best Practices Manual, we have endeavored to place our GEO-SEQ findings in a practical context and format that will be useful to readers interested in project implementation. The overall objective of this Manual is to …
Date: October 23, 2004
Creator: Benson, Sally M.; Myer, Larry R.; Oldenburg, Curtis M.; Doughty, Christine A.; Pruess, Karsten; Lewicki, Jennifer et al.
Object Type: Report
System: The UNT Digital Library
Savannah River Ecology Laboratory FY2006 Annual Technical Progress Report (open access)

Savannah River Ecology Laboratory FY2006 Annual Technical Progress Report

FY2006 annual report of research conducted by the Savannah River Ecology Laboratory, a research unit of the University of Georgia operating on the Savannah River Site in Aiken, County, SC.
Date: October 23, 2006
Creator: Bertsch, Paul M.
Object Type: Report
System: The UNT Digital Library
PERFORMANCE TESTING OF SPRING ENERGIZED C-RINGS FOR USE IN RADIOACTIVE MATERIAL PACKAGINGS CONTAINING TRITIUM (open access)

PERFORMANCE TESTING OF SPRING ENERGIZED C-RINGS FOR USE IN RADIOACTIVE MATERIAL PACKAGINGS CONTAINING TRITIUM

This paper describes the sealing performance testing and results of silver-plated inconel Spring Energized C-Rings used for tritium containment in radioactive shipping packagings. The test methodology used follows requirements of the American Society of Mechanical Engineers (ASME) summarized in ASME Pressure Vessel Code (B&PVC), Section V, Article 10, Appendix IX (Helium Mass Spectrometer Test - Hood Technique) and recommendations by the American National Standards Institute (ANSI) described in ANSI N14.5-1997. The tests parameters bound the predicted structural and thermal responses from conditions defined in the Code of Federal Regulations 10 CFR 71. The testing includes an evaluation of the effects of pressure, temperature, flange deflection, surface roughness, permeation, closure torque, torque sequencing and re-use on performance of metal C-Ring seals.
Date: October 23, 2007
Creator: Blanton, P & Kurt Eberl, K
Object Type: Article
System: The UNT Digital Library
Small scale anisotropies of UHECRs from super-heavy halo dark matter (open access)

Small scale anisotropies of UHECRs from super-heavy halo dark matter

The decay of very heavy metastable relics of the Early Universe can produce ultra-high energy cosmic rays (UHECRs) in the halo of our own Galaxy. In this model, no Greisen-Zatsepin-Kuzmin cutoff is expected because of the short propagation distances. They show here that, as a consequence of the hierarchical build up of the halo, this scenario predicts the existence of small scale anisotropies in the arrival directions of UHECRs, in addition to a large scale anisotropy, known from previous studies. They also suggest some other observable consequences of this scenario which will be testable with upcoming experiments, as Auguer, EUSO and OWL.
Date: October 23, 2001
Creator: Blasi, P. & Sheth, R. K.
Object Type: Article
System: The UNT Digital Library
Aerosol sample preparation methods for X-ray diffractive imaging: Size-selected spherical nanoparticles on silicon nitride foils (open access)

Aerosol sample preparation methods for X-ray diffractive imaging: Size-selected spherical nanoparticles on silicon nitride foils

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Date: October 23, 2006
Creator: Bogan, M. J.; Benner, W. H.; Hau-Riege, S.; Chapman, H. & Frank, M.
Object Type: Article
System: The UNT Digital Library
KENO3D Visualization Tool for KENO V.a and KENO-VI (open access)

KENO3D Visualization Tool for KENO V.a and KENO-VI

Criticality safety analyses often require detailed modeling of complex geometries. Effective visualization tools can enhance checking the accuracy of these models. This report describes the KENO3D visualization tool developed at the Oak Ridge National Laboratory (ORNL) to provide interactive visualization of KENO V.a and KENO-VI criticality safety models. The development of KENO3D is part of the current efforts to enhance the SCALE (Standardized Computer Analyses for Licensing Evaluations) computer software system.
Date: October 23, 2000
Creator: Bowman, S. M. & Horwedel, J. E.
Object Type: Article
System: The UNT Digital Library
Production of High Value Fluorine Gases for the Semiconductor Industry (open access)

Production of High Value Fluorine Gases for the Semiconductor Industry

The chemistry to manufacture high purity GeF{sub 4} and WF{sub 6} for use in the semiconductor industry using Starmet's new fluorine extraction technology has been developed. Production of GeF{sub 4} was established using a tube-style reactor system where conversion yields as high as 98.1% were attained for the reaction between and GeO{sub 2}. Collection of the fluoride gas improved to 97.7% when the reactor sweep gas contained a small fraction of dry air (10-12 vol%) along with helium. The lab-synthesized product was shown to contain the least amount of infrared active and elemental impurities when compared with a reference material certified at 99.99% purity. Analysis of the ''as-produced'' gas using ICP-MS showed that uranium could not be detected at a detection limit of 0.019ppm-wt. A process to make WF{sub 6} from WO{sub 2}, and UF{sub 4}, produced a WOF{sub 4} intermediate, which proved difficult to convert to tungsten hexafluoride using titanium fluoride as a fluorinating agent.
Date: October 23, 2003
Creator: Bulko, J. B.
Object Type: Report
System: The UNT Digital Library
Regulatory Off-Gas Analysis from the Evaporation of Hanford Simulated Waste Spiked with Organic Compounds (open access)

Regulatory Off-Gas Analysis from the Evaporation of Hanford Simulated Waste Spiked with Organic Compounds

After strontium/transuranics removal by precipitation followed by cesium/technetium removal by ion exchange, remaining low activity waste in the Hanford River Protection Project Waste Treatment Plant is to be concentrated by evaporation prior to being mixed with glass formers and vitrified. To provide a technical basis to permit the waste treatment facility, a relatively organic-rich Hanford Tank 241-AN-107 waste simulant was spiked with 14 target volatile, semi-volatile and pesticide compounds, and evaporated under vacuum in a bench-scale natural circulation evaporator fitted with an industrial stack off-gas sampler at the Savannah River Technology Center. An evaporator material balance for the target organics was calculated by combining liquid stream mass and analytical data with off-gas emissions estimates obtained using EPA SW-846 Methods. Volatile and light semi-volatile organic compounds in the waste simulant were found to largely exit through the condenser vent, while heavier semi-volatiles and pesticides generally remain in the evaporator concentrate. An OLI Environmental Simulation Program evaporator model successfully predicted operating conditions and the experimental distribution of the fed target organics exiting in the concentrate, condensate and off-gas streams with the exception of a few semi-volatile and pesticide compounds. Comparison with Henry's Law predictions suggests the OLI ESP model is constrained by …
Date: October 23, 2003
Creator: Calloway, T.B. Jr.
Object Type: Article
System: The UNT Digital Library
Hydrogen Transport in Copper (open access)

Hydrogen Transport in Copper

Hydrogen interaction with oxygen in copper exerts a significant influence on the apparent hydrogen diffusivity and the quantity of hydrogen absorbed. Correlation of the amount of absorbed tritium with oxygen content and dependence of permeation transients on both oxygen content and prior treatment indicate that both reversible and irreversible interactions occur between hydrogen and dissolved oxygen. This paper discusses results of that study.
Date: October 23, 2001
Creator: Caskey, G. R., Jr.
Object Type: Article
System: The UNT Digital Library
From nuclei to hypernuclei: A retrospective view of medium energy physics at Brookhaven (open access)

From nuclei to hypernuclei: A retrospective view of medium energy physics at Brookhaven

A new frontier in physics originated with programs at two Brookhaven National Laboratory facilities--the Cosmotron and the Alternating Gradient Synchrotron. The development of this frontier over a half century is described, as it turned from conventional nuclear physics to the hypernuclei and the study of strange matter.
Date: October 23, 2000
Creator: Chrien, R. E.
Object Type: Article
System: The UNT Digital Library
Limits on a muon flux from Kaluza-Klein dark matter annihilations in the Sun from the IceCube 22-string detector (open access)

Limits on a muon flux from Kaluza-Klein dark matter annihilations in the Sun from the IceCube 22-string detector

A search for muon neutrinos from Kaluza-Klein dark matter annihilations in the Sun has been performed with the 22-string configuration of the IceCube neutrino detector using data collected in 104.3 days of live-time in 2007. No excess over the expected atmospheric background has been observed. Upper limits have been obtained on the annihilation rate of captured lightest Kaluza-Klein particle (LKP) WIMPs in the Sun and converted to limits on the LKP-proton cross-sections for LKP masses in the range 250 - 3000 GeV. These results are the most stringent limits to date on LKP annihilation in the Sun.
Date: October 23, 2009
Creator: Collaboration, IceCube; Abbasi, R. & al., et
Object Type: Article
System: The UNT Digital Library
Final optics damage inspection (FODI) for the National Ignition Facility (open access)

Final optics damage inspection (FODI) for the National Ignition Facility

The National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory (LLNL) will routinely fire high energy shots (approaching 10 kJ per beamline) through the final optics, located on the target chamber. After a high fluence shot, exceeding 4J/cm2 at 351 nm wavelength, the final optics will be inspected for laser-induced damage. The FODI (Final Optics Damage Inspection) system has been developed for this purpose, with requirements to detect laser-induced damage initiation and to track and size it's the growth to the point at which the optic is removed and the site mitigated. The FODI system is the 'corner stone' of the NIF optic recycle strategy. We will describe the FODI system and discuss the challenges to make optics inspection a routine part of NIF operations.
Date: October 23, 2007
Creator: Conder, A.; Alger, T.; Azevedo, S.; Chang, J.; Glenn, S.; Kegelmeyer, L. et al.
Object Type: Article
System: The UNT Digital Library
Crawler Acquisition and Testing Demonstration Project Management Plan (open access)

Crawler Acquisition and Testing Demonstration Project Management Plan

If the crawler based retrieval system is selected, this project management plan identifies the path forward for acquiring a crawler/track pump waste retrieval system, and completing sufficient testing to support deploying the crawler for as part of a retrieval technology demonstration for Tank 241-C-104. In the balance of the document, these activities will be referred to as the Crawler Acquisition and Testing Demonstration. During recent Tri-Party Agreement negotiations, TPA milestones were proposed for a sludge/hard heel waste retrieval demonstration in tank C-104. Specifically one of the proposed milestones requires completion of a cold demonstration of sufficient scale to support final design and testing of the equipment (M-45-03G) by 6/30/2004. A crawler-based retrieval system was one of the two options evaluated during the pre-conceptual engineering for C-104 retrieval (RPP-6843 Rev. 0). The alternative technology procurement initiated by the Hanford Tanks Initiative (HTI) project, combined with the pre-conceptual engineering for C-104 retrieval provide an opportunity to achieve compliance with the proposed TPA milestone M-45-03H. This Crawler Acquisition and Testing Demonstration project management plan identifies the plans, organizational interfaces and responsibilities, management control systems, reporting systems, timeline and requirements for the acquisition and testing of the crawler based retrieval system. This project management …
Date: October 23, 2000
Creator: DEFIGH-PRICE, C.
Object Type: Report
System: The UNT Digital Library