Deep Resistivity Structure of Rainier Mesa-Shoshone Mountain, Nevada Test Site, Nevada (open access)

Deep Resistivity Structure of Rainier Mesa-Shoshone Mountain, Nevada Test Site, Nevada

The U. S. Department of Energy (DOE) and the National Nuclear Security Administration (NNSA) at their Nevada Site Office (NSO) are addressing groundwater contamination resulting from historical underground nuclear testing through the Environmental Management (EM) program and, in particular, the Underground Test Area (UGTA) project. During 2005, the U.S. Geological Survey (USGS), funded by the DOE and NNSA-NSO, collected and processed data from twenty-six Magnetotelluric (MT) and Audio-Magnetotelluric (AMT) sites at the Nevada Test Site. Data stations were located in and near Rainier Mesa and Shoshone Mountain to assist in characterizing the pre-Tertiary geology in those areas. These new stations extend to the west the hydrogeologic study that was conducted in Yucca Flat in 2003. This work has helped to refine the character, thickness, and lateral extent of pre Tertiary confining units. In particular, a major goal has been to define the upper clastic confining unit (UCCU – late Devonian to Mississippian-age siliciclastic rocks assigned to the Eleana Formation and Chainman Shale(Bechtel Nevada, 2006)) in the Yucca Flat area and west towards Shoshone Mountain in the south, east of Buckboard Mesa, and onto Rainier Mesa in the north. The Nevada Test Site magnetotelluric data interpretation presented in this report includes …
Date: December 12, 2006
Creator: Asch, Theodore H.; Rodriguez, Brian D.; Sampson, Jay A.; Williams, Jackie M. & Deszcz-Pan, Maryla
Object Type: Report
System: The UNT Digital Library
Measurement of the B0 to \pi l^+ \nu Form-Factor Shape and Branching Fraction, and Determination of |V_{ub}| with a Loose Neutrino Reconstruction Technique (open access)

Measurement of the B0 to \pi l^+ \nu Form-Factor Shape and Branching Fraction, and Determination of |V_{ub}| with a Loose Neutrino Reconstruction Technique

We report the results of a study of the exclusive charmless semileptonic decay, B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}, undertaken with approximately 227 million B{bar B} pairs collected at the {Gamma}(4S) resonance with the BABAR detector. The analysis uses events in which the signal B decays are reconstructed with an innovative loose neutrino reconstruction technique. We obtain partial branching fractions in 12 bins of q{sup 2}, the momentum transfer squared, from which we extract the f{sub +}(q{sup 2}) form-factor shape and the total branching fraction {beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.46 {+-} 0.07{sub stat} {+-} 0.08{sub syst}) x 10{sup -4}. Based on a recent unquenched lattice QCD calculation of the form factor in the range q{sup 2} > 16 GeV2, we find the magnitude of the CKM matrix element |V{sub ub}| to be (4.1 {+-} 0.2{sub stat} {+-} 0.2{sub syst} +0.6 -0.4 FF)x10{sup -3}, where the last uncertainty is due to the normalization of the form factor.
Date: December 12, 2006
Creator: Aubert, B.; Bona, M.; Boutigny, D.; Karyotakis, Y.; Lees, J. P.; Poireau, V. et al.
Object Type: Article
System: The UNT Digital Library
Exemptions from Environmental Law fora the Department of Defense: Background and Issues for Congress (open access)

Exemptions from Environmental Law fora the Department of Defense: Background and Issues for Congress

This report provides Background and Issues for Congress on Exemptions from Environmental Law for the Department of Defense. several environmental statutes contain national security exemptions which is a department of defense can obtain on a case by case basis.
Date: December 12, 2006
Creator: Bearden, David M.
Object Type: Report
System: The UNT Digital Library
Development of a Focusing DIRC (open access)

Development of a Focusing DIRC

Benefiting from the recent introduction of new fast vacuum-based photon detectors with a transit time spread of {sigma}{sub TTS} {approx} 30-150 ps, we are developing a novel RICH detector capable of correcting the chromatic error through good time measurements; we believe that this is the first time such a technique has been demonstrated. We have built and successfully tested a particle identification detector called ''Focusing DIRC''. The concept of the prototype is based on the BaBar DIRC, with several important improvements: (a) much faster pixelated photon detectors based on Burle MCP-PMTs and Hamamatsu MaPMTs, (b) a focusing mirror which allows the photon detector to be smaller and less sensitive to background in future applications, (c) electronics allowing the measurement of single photon timing to better than {sigma} {approx} 100-200ps, which allows a correction of the chromatic error. The detector was tested in a SLAC 10GeV/c electron test beam. This detector concept could be used for particle identification at Super B-factory, ILC, GlueX, Panda, etc.
Date: December 12, 2006
Creator: Benitez, J.; Bedajanek, I.; Leith, D.W.G.S.; Mazaheri, G.; Ratcliff, B.; Suzuki, K. et al.
Object Type: Article
System: The UNT Digital Library
Evaluation of the Transient Hydrologic Source Term for the Cambric Underground Nuclear Test at Frenchman Flat, Nevada test Site (open access)

Evaluation of the Transient Hydrologic Source Term for the Cambric Underground Nuclear Test at Frenchman Flat, Nevada test Site

The objective of Phase II HST work is to develop a better understanding of the evolution of the HST for 1,000 years at the CAMBRIC underground nuclear test site in Frenchman Flat at the NTS. This work provides a better understanding of activities as they actually occurred, incorporates improvements based on recent data acquisition, and provides a basis to use the CAMBRIC site for model validation and monitoring activities as required by the UGTA Project. CAMBRIC was the only test in Frenchman Flat detonated under the water table and best represents a fully saturated environment. These simulations are part of a broad Phase II Frenchman Flat Corrective Action Unit (CAU) flow and transport modeling effort being conducted by the Department of Energy (DOE) Underground Test Area (UGTA) Project. HST simulations provide, either directly or indirectly, the source term used in the CAU model to calculate a contaminant boundary. Work described in this report augments Phase I HST calculations at CAMBRIC conducted by Tompson et al. (1999) and Pawloski et al. (2001). Phase II HST calculations have been organized to calculate source terms under two scenarios: (1) A representation of the transient flow and radionuclide release behavior at the CAMBRIC site …
Date: December 12, 2006
Creator: Carle, S. F.; Maxwell, R. M.; Pawloski, G. A.; Shumaker, D. E.; Tompson, A. B. & Zavarin, M.
Object Type: Report
System: The UNT Digital Library
Disorder and size effects on Kondo interactions and magnetic correlations in CePt2 nanoscrystals (open access)

Disorder and size effects on Kondo interactions and magnetic correlations in CePt2 nanoscrystals

The evolution of the Kondo effect and magnetic correlations with size reduction in CePt{sub 2} nanoparticles (3.1-26 nm) is studied by analysis of the temperature-dependent specific heat and magnetic susceptibility. The antiferromagnetic correlations diminish with size reduction. The Kondo effect predominates at small particle size with trivalent, small Kondo temperature (T{sub K}) magnetic regions coexisting with strongly mixed valent, large T{sub K} nonmagnetic regions. We discuss the role of structural disorder, background density of states and the electronic quantum size effect on the results.
Date: December 12, 2006
Creator: Chen, Y. Y.; Huang, P. H.; Ou, M. N.; Wang, C. R.; Yao, Y. D.; Lee, T. K. et al.
Object Type: Article
System: The UNT Digital Library
Water Quality: Implementing the Clean Water Act (open access)

Water Quality: Implementing the Clean Water Act

None
Date: December 12, 2006
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Acceptance Criteria Framework for Autonomous Biological Detectors (open access)

Acceptance Criteria Framework for Autonomous Biological Detectors

The purpose of this study was to examine a set of user acceptance criteria for autonomous biological detection systems for application in high-traffic, public facilities. The test case for the acceptance criteria was the Autonomous Pathogen Detection System (APDS) operating in high-traffic facilities in New York City (NYC). However, the acceptance criteria were designed to be generally applicable to other biological detection systems in other locations. For such detection systems, ''users'' will include local authorities (e.g., facility operators, public health officials, and law enforcement personnel) and national authorities [including personnel from the Department of Homeland Security (DHS), the BioWatch Program, the Centers for Disease Control and Prevention (CDC), and the Federal Bureau of Investigation (FBI)]. The panel members brought expertise from a broad range of backgrounds to complete this picture. The goals of this document are: (1) To serve as informal guidance for users in considering the benefits and costs of these systems. (2) To serve as informal guidance for developers in understanding the needs of users. In follow-up work, this framework will be used to systematically document the APDS for appropriateness and readiness for use in NYC.
Date: December 12, 2006
Creator: Dzenitis, J M
Object Type: Report
System: The UNT Digital Library
The WTO, Intellectual Property Rights, and the Access to Medicines Controversy (open access)

The WTO, Intellectual Property Rights, and the Access to Medicines Controversy

None
Date: December 12, 2006
Creator: Fergusson, Ian F.
Object Type: Report
System: The UNT Digital Library
Report on New Capabilities for the Purple Development Environment (open access)

Report on New Capabilities for the Purple Development Environment

As part of the deliverables for the Development Environment for Purple, additional capabilities to improve the tools offerings and to address unique Purple system requirements, such as increased processor count, were expected. This report details some of the new capabilities that have been incorporated into the development environment tools for Purple. The shift on Purple to 64-bit applications (from 32-bit on White) initially broke many debugging and memory tools. Most tools were updated to support 64 bit well before Purple was delivered to LLNL, but the company that provided the popular heavy-weight 32-bit AIX memory tool, ZeroFault, was reluctant to port to 64 bit due to perceived lack of market. LLNL tried offering financial incentives to the ZeroFault developers, which were turned down, but eventually they did give vague promises to try to port to AIX 64-bit mode when they got time. The ZeroFault developers have been making intermittent and very slow progress over the last two plus years, but despite getting close, have not released a version of ZeroFault that yet meets our needs for 64-bit applications. However, given the critical need for memory tools and the uncertainty of ZeroFault development, other memory tool options were actively pursued and …
Date: December 12, 2006
Creator: Futral, W S; Chambreau, C M; Gyllenhaal, J C & Wolfe, M E
Object Type: Report
System: The UNT Digital Library
Report on Challenges and Resolutions for the Purple Development Environment (open access)

Report on Challenges and Resolutions for the Purple Development Environment

Previous AIX development environment experience with ASC White and Early Delivery systems UV and UM was leveraged to provide a smooth and robust transition to the Purple development environment. Still, there were three major changes that initially caused serious problems for Purple users. The first was making 64-bit builds of executables the default instead of 32-bit. The second was requiring all executables to use large page memory. The third was the phase-out of the popular, but now defunct, third-party C++ compiler KCC, which required the migration of many codes to IBM's xlC C++ compiler. On Purple, the default build environment changed from 32-bit builds to 64-bit builds in order to enable executables to use the 4GB per processor (32GB per node) memory available, and in order for the MPI library to do collective optimizations that required the larger 64-bit address space. The 64-bit build environment was made default by setting the IBM environment variable OBJECT{_}MODE to 64 and wrapping third-party software (mainly the gnu compilers) in order to make them handle OBJECT{_}MODE properly. Because not all applications could port to 64-bit right away, (usually due to third-party constraints, such as python not supporting 64-bit AIX builds until very recently), 32-bit …
Date: December 12, 2006
Creator: Futral, W S; Gyllenhaal, J C; Wolfe, M E & Chambreau, C M
Object Type: Report
System: The UNT Digital Library
Immigration Consequences of Criminal Activity (open access)

Immigration Consequences of Criminal Activity

None
Date: December 12, 2006
Creator: Garcia, Michael J.
Object Type: Report
System: The UNT Digital Library
Pay-for-Performance in Health Care (open access)

Pay-for-Performance in Health Care

None
Date: December 12, 2006
Creator: Hahn, Jim
Object Type: Report
System: The UNT Digital Library
Iranian Nuclear Sites (open access)

Iranian Nuclear Sites

This report describes Iran's known nuclear sites listed in official International Atomic Energy Agency (IAEA) reports and includes a map with the location of the nuclear facilities.
Date: December 12, 2006
Creator: Hassan, Hussein D.
Object Type: Report
System: The UNT Digital Library
International Conference on Multiscale Methods and Partial Differential Equations. (open access)

International Conference on Multiscale Methods and Partial Differential Equations.

The International Conference on Multiscale Methods and Partial Differential Equations (ICMMPDE for short) was held at IPAM, UCLA on August 26-27, 2005. The conference brought together researchers, students and practitioners with interest in the theoretical, computational and practical aspects of multiscale problems and related partial differential equations. The conference provided a forum to exchange and stimulate new ideas from different disciplines, and to formulate new challenging multiscale problems that will have impact in applications.
Date: December 12, 2006
Creator: Hou, Thomas
Object Type: Report
System: The UNT Digital Library
New Synthetic Methods for Hypericum Natural Products (open access)

New Synthetic Methods for Hypericum Natural Products

Organic chemistry has served as a solid foundation for interdisciplinary research areas, such as molecular biology and medicinal chemistry. An understanding of the biological activities and structural elucidations of natural products can lead to the development of clinically valuable therapeutic options. The advancements of modern synthetic methodologies allow for more elaborate and concise natural product syntheses. The theme of this study centers on the synthesis of natural products with particularly challenging structures and interesting biological activities. The synthetic expertise developed here will be applicable to analog syntheses and to other research problems.
Date: December 12, 2006
Creator: Jeon, Insik
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Synthesis, structure, magnetism, and optical properties of theordered mixed-lanthanide sulfides gamma-LnLn'S3 (Ln=La, Ce; Ln'=Er, Tm,Yb) (open access)

Synthesis, structure, magnetism, and optical properties of theordered mixed-lanthanide sulfides gamma-LnLn'S3 (Ln=La, Ce; Ln'=Er, Tm,Yb)

{gamma}-LnLn{prime}S{sub 3} (Ln = La, Ce; Ln{prime} = Er, Tm, Yb) have been prepared as dark red to black single crystals by the reaction of the respective lanthanides with sulfur in a Sb{sub 2}S{sub 3} flux at 1000 C. This isotypic series of compounds adopts a layered structure that consists of the smaller lanthanides (Er, Tm, and Yb) bound by sulfide in six- and seven-coordinate environments that are connected together by the larger lanthanides (La and Ce) in eight- and nine-coordinate environments. The layers can be broken down into three distinct one-dimensional substructures containing three crystallographically unique Ln{prime} centers. The first of these is constructed from one-dimensional chains of edge-sharing [Ln{prime}S{sub 7}] monocapped trigonal prisms that are joined to equivalent chains via edge-sharing to yield ribbons. There are parallel chains of [Ln{prime}S{sub 6}] distorted octahedra that are linked to the first ribbons through corner-sharing. These latter units also share corners with a one-dimensional ribbon composed of parallel chains of [Ln{prime}S{sub 6}] polyhedra that edge-share both in the direction of chain propagation and with adjacent identical chains. Magnetic susceptibility measurements show Curie-Weiss behavior from 2 to 300 K with antiferromagnetic coupling, and no evidence for magnetic ordering. The {theta}{sub p} values …
Date: December 12, 2006
Creator: Jin, Geng Bang; Choi, Eun Sang; Guertin, Robert P.; Brooks, James S.; Bray, Travis H.; Booth, Corwin H. et al.
Object Type: Article
System: The UNT Digital Library
Mechanistic Selection and Growth of Twinned Bicrystalline Primary Si in Near Eutectic Al-Si Alloys (open access)

Mechanistic Selection and Growth of Twinned Bicrystalline Primary Si in Near Eutectic Al-Si Alloys

Morphological evolution and selection of angular primary silicon is investigated in near-eutectic Al-Si alloys. Angular silicon arrays are grown directionally in a Bridgman furnace at velocities in the regime of 10{sup -3} m/sec and with a temperature gradient of 7.5 x 10{sup 3} K/m. Under these conditions, the primary Si phase grows as an array of twinned bicrystalline dendrites, where the twinning gives rise to a characteristic 8-pointed star-shaped primary morphology. While this primary Si remains largely faceted at the growth front, a complex structure of coherent symmetric twin boundaries enables various adjustment mechanisms which operate to optimize the characteristic spacings within the primary array. In the work presented here, this primary silicon growth morphology is examined in detail. In particular, this thesis describes the investigation of: (1) morphological selection of the twinned bicrystalline primary starshape morphology; (2) primary array behavior, including the lateral propagation of the starshape grains and the associated evolution of a strong <100> texture; (3) the detailed structure of the 8-pointed star-shaped primary morphology, including the twin boundary configuration within the central core; (4) the mechanisms of lateral propagation and spacing adjustment during array evolution; and (5) the thermosolutal conditions (i.e. operating state) at the primary …
Date: December 12, 2006
Creator: Jung, Choonho
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Issues in IIA Uplifting (open access)

Issues in IIA Uplifting

Moduli stabilization in the type IIA massive string theory so far was achieved only in the AdS vacua. The uplifting to dS vacua has not been performed as yet: neither the analogs of type IIB anti-D3 brane at the tip of the conifold, nor the appropriate D-terms have been identified. The hope was recently expressed that the F-term uplifting may work. We investigate this possibility in the context of a simplified version of the type IIA model developed in hep-th/0505160 and find that the F-term does not uplift the AdS vacua to dS vacua with positive CC. Thus it remains a challenging task to find phenomenologically acceptable vacua in the type IIA string theory.
Date: December 12, 2006
Creator: Kallosh, Renata & Soroush, Masoud
Object Type: Report
System: The UNT Digital Library
Open Access Publishing and Citation Archives: Background and Controversy (open access)

Open Access Publishing and Citation Archives: Background and Controversy

This report begins with an inventory of basic information: definitions and guides to histories of the growth of open access publishing and citation archives and descriptions of selected major open access activities. It moves on to summarize major points of difference between proponents and opponents of nongovernmental open access publishing and databases, and then highlights federal, including National Institutes of Health (NIH), open access activities and contentious issues surrounding these developments. The report also briefly describes open access developments in the United Kingdom (where a number of governmental and nongovernmental initiatives have occurred) and in the international arena. Finally, controversial issues which could receive attention the 110th Congress are summarized.
Date: December 12, 2006
Creator: Knezo, Genevieve J.
Object Type: Report
System: The UNT Digital Library
Determination of Optimum Conditions for Distinguishing the Pulse Height Distributions of Atomic and Polyatomic Ions (open access)

Determination of Optimum Conditions for Distinguishing the Pulse Height Distributions of Atomic and Polyatomic Ions

This work explored the use of pulse height distributions (PHD) from multiplier-type detectors as a means of detecting and eliminating the effects of polyatomic interferences in secondary ion mass spectrometry (SIMS). We explored the behavior of PHD for {sup 235}U{sup +}, {sup 208}Pb{sup 27}Al{sup +} and {sup 207}Pb{sup 28}Si{sup +}, all with a nominal mass-to-charge ratio of 235. In every case, the distribution for the atomic ion ({sup 235}U{sup +}) was clearly shifted relative to the distributions for {sup 208}Pb{sup 27}Al{sup +} and {sup 207}Pb{sup 28}Si{sup +}. When the first surface of the detector is metallic in character, the polyatomic ions are shifted to larger pulse heights relative to the atomic ion. When the first surface of the detector is oxide in character, the atomic ion is shifted to larger pulse heights relative to the polyatomic ions. The relative positioning appear to be stable for a given detector over time at the same secondary ion impact energy. Consequently, it appears to be feasible to use PHD data to detect interfering polyatomic ions and eliminate their deleterious effects using peak deconvolution techniques. Consequently, the updated Ultrafast RAE detector will be designed to make the pulse height information available to the data …
Date: December 12, 2006
Creator: Kristo, M J
Object Type: Report
System: The UNT Digital Library
Broadband Internet Access and the Digital Divide: Federal Assistance Programs (open access)

Broadband Internet Access and the Digital Divide: Federal Assistance Programs

Some policymakers, believing that disparities in broadband access across American society could have adverse economic and social consequences on those left behind, assert that the federal government should play a more active role to avoid a “digital divide” in broadband access. One approach is for the federal government to provide financial assistance to support broadband deployment in underserved areas. Others, however, believe that federal assistance for broadband deployment is not appropriate. Some opponents question the reality of the “digital divide,” and argue that federal intervention in the broadband marketplace would be premature and, in some cases, counterproductive.
Date: December 12, 2006
Creator: Kruger, Lennard G. & Gilroy, Angele A.
Object Type: Report
System: The UNT Digital Library
Single Molecule Screening of Disease DNA Without Amplification (open access)

Single Molecule Screening of Disease DNA Without Amplification

The potential of single molecule detection as an analysis tool in biological and medical fields is well recognized today. This fast evolving technique will provide fundamental sensitivity to pick up individual pathogen molecules, and therefore contribute to a more accurate diagnosis and a better chance for a complete cure. Many studies are being carried out to successfully apply this technique in real screening fields. In this dissertation, several attempts are shown that have been made to test and refine the application of the single molecule technique as a clinical screening method. A basic applicability was tested with a 100% target content sample, using electrophoretic mobility and multiple colors as identification tools. Both electrophoretic and spectral information of individual molecule were collected within a second, while the molecule travels along the flow in a capillary. Insertion of a transmission grating made the recording of the whole spectrum of a dye-stained molecule possible without adding complicated instrumental components. Collecting two kinds of information simultaneously and combining them allowed more thorough identification, up to 98.8% accuracy. Probing mRNA molecules with fluorescently labeled cDNA via hybridization was also carried out. The spectral differences among target, probe, and hybrid were interpreted in terms of dispersion …
Date: December 12, 2006
Creator: Lee, Ji-Young
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Effects on U.S. Farm Workers of an Agricultural Guest Worker Program (open access)

The Effects on U.S. Farm Workers of an Agricultural Guest Worker Program

This report discusses the debate concerning an agricultural guest worker program and the impact such a program might have on U.S. workers. Guest worker programs are meant to assure employers (e.g., fruit, vegetable, and horticultural specialty growers) of an adequate supply of labor when and where it is needed, while not adding permanent residents to the U.S. population. They include mechanisms -- such as the H-2A program's labor certification process -- intended to avoid adversely affecting the wages and working conditions of similarly-employed U.S. workers.
Date: December 12, 2006
Creator: Levine, Linda
Object Type: Report
System: The UNT Digital Library