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Environmental Information: EPA Actions Could Reduce the Availability of Environmental Information to the Public (open access)

Environmental Information: EPA Actions Could Reduce the Availability of Environmental Information to the Public

Testimony issued by the Government Accountability Office with an abstract that begins "U.S. industry uses billions of pounds of chemicals to produce the nation's goods and services. Releases of these chemicals during use or disposal can harm human health and the environment. The Emergency Planning and Community Right-to-Know Act of 1986 requires facilities that manufacture, process, or otherwise use more than specified amounts of nearly 650 toxic chemicals to report their releases to water, air, and land. The Environmental Protection Agency (EPA) makes this data available to the public in the Toxics Release Inventory (TRI). Since 1995, facilities may submit a brief certification statement (Form A), in lieu of the detailed Form R report, if their releases of specific chemicals do not exceed 500 pounds a year. In January 2007, EPA finalized a proposal to increase that threshold to 2,000 pounds, quadrupling what facilities can release before they must disclose their releases and other waste management practices. Today's testimony addresses (1) EPA's development of the proposal to change the TRI Form A threshold from 500 to 2,000 pounds and (2) the impact these changes may have on data available to the public. It also provides an update to our 2005 …
Date: February 6, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
Homeland Security: Management and Programmatic Challenges Facing the Department of Homeland Security (open access)

Homeland Security: Management and Programmatic Challenges Facing the Department of Homeland Security

Testimony issued by the Government Accountability Office with an abstract that begins "The Department of Homeland Security (DHS) plays a key role in leading and coordinating--with stakeholders in the federal, state, local, and private sectors--the nation's homeland security efforts. GAO has conducted numerous reviews of DHS management functions as well as programs including transportation and border security, immigration enforcement and service delivery, and disaster preparation and response. This testimony addresses why GAO designated DHS's implementation and transformation as a high-risk area, management challenges facing DHS, programmatic challenges facing DHS, and actions DHS should take to strengthen its implementation and transformation efforts."
Date: February 6, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library

Senior Recital: 2007-02-06 - Daniel Robert Kirkpatrick, percussion

Access: Use of this item is restricted to the UNT Community
A senior recital presented at the UNT College of Music Recital Hall in partial fulfillment of the Bachelor of Music (BM) degree.
Date: February 6, 2007
Creator: Kirkpatrick, Daniel Robert
Object Type: Sound
System: The UNT Digital Library
Volume Independence in Large Nc QCD-like Gauge Theories (open access)

Volume Independence in Large Nc QCD-like Gauge Theories

Volume independence in large N{sub c} gauge theories may be viewed as a generalized orbifold equivalence. The reduction to zero volume (or Eguchi-Kawai reduction) is a special case of this equivalence. So is temperature independence in confining phases. A natural generalization concerns volume independence in ''theory space'' of quiver gauge theories. In pure Yang-Mills theory, the failure of volume independence for sufficiently small volumes (at weak coupling) due to spontaneous breaking of center symmetry, together with its validity above a critical size, nicely illustrate the symmetry realization conditions which are both necessary and sufficient for large N{sub c} orbifold equivalence. The existence of a minimal size below which volume independence fails also applies to Yang-Mills theory with antisymmetric representation fermions [QCD(AS)]. However, in Yang-Mills theory with adjoint representation fermions [QCD(Adj)], endowed with periodic boundary conditions, volume independence remains valid down to arbitrarily small size. In sufficiently large volumes, QCD(Adj) and QCD(AS) have a large N{sub c} ''orientifold'' equivalence, provided charge conjugation symmetry is unbroken in the latter theory. Therefore, via a combined orbifold-orientifold mapping, a well-defined large N{sub c} equivalence exists between QCD(AS) in large, or infinite, volume and QCD(Adj) in arbitrarily small volume. Since asymptotically free gauge theories, such …
Date: February 6, 2007
Creator: Kovtun, Pavel; Unsal, Mithat & Yaffe, Laurence G.
Object Type: Article
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 38, No. 1, Ed. 1 Tuesday, February 6, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 1, Ed. 1 Tuesday, February 6, 2007

Free weekly newspaper that includes business and classified advertising.
Date: February 6, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 38, No. 2, Ed. 1 Tuesday, February 6, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 2, Ed. 1 Tuesday, February 6, 2007

Free weekly newspaper that includes business and classified advertising.
Date: February 6, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 91, No. 65, Ed. 1 Tuesday, February 6, 2007 (open access)

North Texas Daily (Denton, Tex.), Vol. 91, No. 65, Ed. 1 Tuesday, February 6, 2007

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: February 6, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Gasoline Prices: Issues for the 110th Congress (open access)

Gasoline Prices: Issues for the 110th Congress

This report discusses potential issues regarding gasoline prices for the 110th Congress. As prices continued to surge, the continuing crisis renewed attention on some issues that were dropped or compromised in the debate over P.L. 109-58, as well as to a number of initiatives to reduce the impact of high prices on consumers.
Date: February 6, 2007
Creator: Behrens, Carl E. & Glover, Carol
Object Type: Report
System: The UNT Digital Library
GLASS SELECTION STRATEGY: DEVELOPMENT OF US AND KRI TEST MATRICIES (open access)

GLASS SELECTION STRATEGY: DEVELOPMENT OF US AND KRI TEST MATRICIES

High-level radioactive wastes are stored as liquids in underground storage tanks at the Department of Energy's (DOE) Savannah River Site (SRS) and Hanford Reservation. These wastes are to be prepared for permanent disposition in a geologic repository by vitrification with glass forming additives (e.g., frit), creating a waste form with long-term durability. Wastes at SRS are being vitrified in the Defense Waste Processing Facility (DWPF). Vitrification of the wastes stored at Hanford is planned for the Waste Treatment and Immobilization Plant (WTP) when completed. Some of the wastes at SRS, and particularly those at Hanford, contain high concentrations of aluminum, chromium and sulfate. These elements make it more difficult to produce a waste glass with a high waste loading (WL) without crystallization occurring in the glass (either within the melter or upon cooling of the glass), potentially exceeding the solubility limit of critical components, having negative impacts on durability, and/or resulting in the formation of a sulfate salt layer on the molten glass surface. Although the overall scope of the task is focused on all three critical, chemical components, the current work will primarily address the potential for crystallization (e.g., nepheline and/or spinel) in high level waste (HLW) glasses. Recent …
Date: February 6, 2007
Creator: Fox, K; Tommy Edwards, T & David Peeler, D
Object Type: Report
System: The UNT Digital Library
Elucidating the Molecular Basis and Regulation of Chromium(VI) Reduction by Shewanella oneidensis MR-1 and Resistance to Metal Toxicity Using Integrated Biochemical, Genomic and Proteomic Approaches (open access)

Elucidating the Molecular Basis and Regulation of Chromium(VI) Reduction by Shewanella oneidensis MR-1 and Resistance to Metal Toxicity Using Integrated Biochemical, Genomic and Proteomic Approaches

Shewanella oneidensis MR-1 is a model environmental organism that possesses diverse respiratory capacities, including the ability to reduce soluble Cr(VI) to sparingly soluble, less toxic Cr(III). Chromate is a serious anthropogenic pollutant found in subsurface sediment and groundwater environments due to its widespread use in defense and industrial applications. Effective bioremediation of chromate-contaminated sites requires knowledge of the molecular mechanisms and regulation of heavy metal resistance and biotransformation by dissimilatory metal-reducing bacteria. Towards this goal, our ERSP-funded work was focused on the identification and functional analysis of genes/proteins comprising the response pathways for chromate detoxification and/or reduction. Our work utilized temporal transcriptomic profiling and whole-cell proteomic analyses to characterize the dynamic molecular response of MR-1 to an acute chromate shock (up to 90 min) as well as to a 24-h, low-dose exposure. In addition, we have examined the transcriptome of MR-1 cells actively engaged in chromate reduction. These studies implicated the involvement of a functionally undefined DNA-binding response regulator (SO2426) and a putative azoreductase (SO3585) in the chromate stress response of MR-1.
Date: February 6, 2007
Creator: Thompson, Dorothea K. & Hettich, Robert
Object Type: Report
System: The UNT Digital Library
Synthesis and Performance of Fe-based Amorphous Alloys for Nuclear Waste Applications (open access)

Synthesis and Performance of Fe-based Amorphous Alloys for Nuclear Waste Applications

Recent developments in multi-component Fe-based amorphous alloys have shown that these novel materials exhibit outstanding corrosion resistance compared to typical crystalline alloys such as high-performance stainless steels and Ni-based C-22 alloy. During the past decade, amorphous alloy synthesis has advanced to allow for the casting of bulk metallic glasses. In several Fe-based alloy systems it is possible to produce glasses with cooling rates as low as 100 K/s. At such low cooling rates, there is an opportunity to produce amorphous solids through industrial processes such as thermal spray-formed coatings. Moreover, since cooling rates in typical thermal spray processing exceed 1000 K/s, novel alloy compositions can be synthesized to maximize corrosion resistance (i.e. adding Cr and Mo) and to improve radiation compatibility (adding B) and still maintain glass forming ability. The applicability of Fe-based amorphous coatings in typical environments where corrosion resistance and thermal stability are critical issues has been examined in terms of amorphous phase stability and glass-forming ability through a coordinated computational analysis and experimental validation. For example, a wedge casting technique has been applied to examine bulk glass forming alloys by combining multiple thermal probes with a measurement based kinetics analysis and a computational thermodynamics evaluation to elucidate …
Date: February 6, 2007
Creator: Kaufman, L; Perepezko, J & Hildal, K
Object Type: Article
System: The UNT Digital Library
Measurement of CP Asymmetry in B0 to Ks pi0 pi0 Decays (open access)

Measurement of CP Asymmetry in B0 to Ks pi0 pi0 Decays

We present a measurement of the time-dependent CP asymmetry for the neutral B-meson decay into the CP = +1 final state K{sub S}{sup 0}{pi}{sup 0}{pi}{sup 0}, with K{sub S}{sup 0} {yields} {pi}{sup +}{pi}{sup -}. We use a sample of approximately 227 million B-meson pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B-Factory at SLAC. From an unbinned maximum likelihood fit we extract the mixing-induced CP-violation parameter S = 0.72 {+-} 0.71 {+-} 0.08 and the direct CP-violation parameter C = 0.23 {+-} 0.52 {+-} 0.13, where the first uncertainty is statistical and the second systematic.
Date: February 6, 2007
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Demonstration of Enhanced Radiation Drive in Hohlraums Made with High-Z Mixture "Cocktail" Wall Material (open access)

Demonstration of Enhanced Radiation Drive in Hohlraums Made with High-Z Mixture "Cocktail" Wall Material

We present results from experiments, numerical simulations and analytic modeling, demonstrating enhanced hohlraum performance. Care in the fabrication and handling of hohlraums with walls consisting of high-Z mixtures (cocktails) has led to our demonstration, for the first time, of a significant increase in radiation temperature compared to a pure Au hohlraum that is in agreement with predictions and is ascribable to reduced wall losses. This data suggests that a NIF ignition hohlraum made of a U:Au:Dy cocktail should have {approx}17% reduction in wall losses compared to a similar gold hohlraum.
Date: February 6, 2007
Creator: Schein, J; Jones, O; Rosen, M; Dewald, E; Glenzer, S; Gunther, J et al.
Object Type: Article
System: The UNT Digital Library
Floating into Thin Air (open access)

Floating into Thin Air

On May 18, 2005, a giant helium balloon carrying the High Energy Focusing Telescope (HEFT) sailed into the spring sky over the deserts of New Mexico. The spindly steel and aluminum gondola that houses the optics, detectors, and other components of the telescope floated for 25 hours after its launch from Fort Sumner, New Mexico. For 21 of those hours, the balloon was nearly 40 kilometers above Earth's surface--almost four times higher than the altitude routinely flown by commercial jet aircraft. In the upper reaches of Earth's atmosphere, HEFT searched the universe for x-ray sources from highly energetic objects such as binary stars, galaxy clusters, and supermassive black holes. Before landing in Arizona, the telescope observed and imaged a dozen scientific targets by capturing photons emitted from these objects in the high-energy (hard) x-ray range (above 10 kiloelectronvolts). Among these targets were the Crab synchrotron nebula, the black hole Cygnus X-1 (one of the brightest x-ray sources in the sky), and the blazar 3C454.3. The scientific data gathered from these targets are among the first focused hard x-ray images returned from high altitudes.
Date: February 6, 2007
Creator: Hazi, A U
Object Type: Report
System: The UNT Digital Library
Variable VHE gamma-ray emission from Markarian 501 (open access)

Variable VHE gamma-ray emission from Markarian 501

The blazar Markarian 501 (Mrk 501) was observed at energies above 100 GeV with the MAGIC telescope from May through July 2005. The high sensitivity of the instrument enabled the determination of the flux and spectrum of the source on a night-by-night basis. Throughout our observational campaign, the flux from Mrk 501 was found to vary by an order of magnitude, and to be correlated with spectral changes. Intra-night flux variability with flux-doubling times down to 2 minutes was also observed. The strength of variability increased with the energy of the {gamma}-ray photons. The energy spectra were found to harden significantly with increasing flux, and a spectral peak clearly showed up during very active states. The position of the spectral peak seems to be correlated with the source luminosity.
Date: February 6, 2007
Creator: Albert, Jordi
Object Type: Article
System: The UNT Digital Library
FY 2005 Congressional Earmark: The Environmental Institute Fellowship Program (open access)

FY 2005 Congressional Earmark: The Environmental Institute Fellowship Program

Congressional Earmark Funding was used to create a Postdoctoral Environmental Fellowship Program, interdisciplinary Environmental Working Groups, and special initiatives to create a dialogue around the environment at the University of Massachusetts Amherst to mobilize faculty to work together to respond to emerging environmental needs and to build institutional capacity to launch programmatic environmental activities across campus over time. Developing these networks of expertise will enable the University to more effectively and swiftly respond to emerging environmental needs and assume a leadership role in varied environmental fields. Over the course of the project 20 proposals were submitted to a variety of funding agencies involving faculty teams from 19 academic departments; 4 projects were awarded totaling $950,000; special events were organized including the Environmental Lecture Series which attracted more than 1,000 attendees over the course of the project; 75 University faculty became involved in one or more Working Groups (original three Working Groups plus Phase 2 Working Groups); an expertise database was developed with approximately 275 faculty involved in environmental research and education as part of a campus-wide network of environmental expertise; 12 University centers and partners participated; and the three Environmental Fellows produced 3 publications as well as a number of …
Date: February 6, 2007
Creator: Tracey, Sharon & Taupier, Richard
Object Type: Text
System: The UNT Digital Library
Hafnium Resonance Parameter Analysis Using Neutron Capture and Transmission Experiments (open access)

Hafnium Resonance Parameter Analysis Using Neutron Capture and Transmission Experiments

The focus of this work is to determine the resonance parameters for stable hafnium isotopes in the 0.005 - 200 eV region, with special emphasis on the overlapping {sup 176}Hf and {sup 178}Hf resonances near 8 eV. Accurate hafnium cross sections and resonance parameters are needed in order to quantify the effects of hafnium found in zirconium, a metal commonly used in reactors. The accuracy of the cross sections and the corresponding resonance parameters used in current nuclear analysis tools are rapidly becoming the limiting factor in reducing the overall uncertainty on reactor physics calculations. Experiments measuring neutron capture and transmission are routinely performed at the Rensselaer Polytechnic Institute (RPI) LINAC using the time-of flight technique. {sup 6}Li glass scintillation detectors were used for transmission experiments at flight path lengths of 15 and 25 m, respectively. Capture experiments were performed using a sixteen section NaI multiplicity detector at a flight path length of 25 m. These experiments utilized several thicknesses of metallic and isotope-enriched liquid Hf samples. The liquid Hf samples were designed to provide information on the {sup 176}Hf and {sup 178}Hf contributions to the 8 eV doublet without saturation. Data analyses were performed using the R-matrix Bayesian code …
Date: February 6, 2007
Creator: Trbovich, M J; Barry, D P; Slovacek, R E; Danon, Y; Block, R C; Francis, N C et al.
Object Type: Report
System: The UNT Digital Library
Effects of Boundary Conditions and Flow on the Kink Instability in a Cylindrical Plasma Column (open access)

Effects of Boundary Conditions and Flow on the Kink Instability in a Cylindrical Plasma Column

An experimental investigation of the kink instability is presented in a linear plasma column where one end is line-tied to the plasma source, and the other end is not line-tied and therefore free to slide over the surface of the end-plate. This latter boundary condition is a result of plasma sheath resistance that insulates, at least partially, the plasma from the end-plate. The helical m = 1 kink mode is observed to grow when the plasma current exceeds a threshold and, close to the criticality, is characterized by an axial mode structure with maximum displacement at the free axial boundary. Azimuthal rotation of the mode is observed such that the helically kinked column always screws into the free axial boundary. The kink mode structure, rotation frequency and instability threshold are accurately reproduced by a recent kink theory [D. D. Ryutov, et al., Phys. Plasmas 13, 032105 (2006)], which includes axial plasma flow and one end of the plasma column that is free to move due to a perfect non-line-tying boundary condition which is experimentally verified. A brief review of the kink theory and its predictions for the boundary conditions relevant in the present experiments are presented.
Date: February 6, 2007
Creator: Furno, I.; Intrator, T. P.; Lapenta, G.; Dorf, L. & Ryutov, D. D.
Object Type: Article
System: The UNT Digital Library
Keeping an Eye on the Prize (open access)

Keeping an Eye on the Prize

Setting performance goals is part of the business plan for almost every company. The same is true in the world of supercomputers. Ten years ago, the Department of Energy (DOE) launched the Accelerated Strategic Computing Initiative (ASCI) to help ensure the safety and reliability of the nation's nuclear weapons stockpile without nuclear testing. ASCI, which is now called the Advanced Simulation and Computing (ASC) Program and is managed by DOE's National Nuclear Security Administration (NNSA), set an initial 10-year goal to obtain computers that could process up to 100 trillion floating-point operations per second (teraflops). Many computer experts thought the goal was overly ambitious, but the program's results have proved them wrong. Last November, a Livermore-IBM team received the 2005 Gordon Bell Prize for achieving more than 100 teraflops while modeling the pressure-induced solidification of molten metal. The prestigious prize, which is named for a founding father of supercomputing, is awarded each year at the Supercomputing Conference to innovators who advance high-performance computing. Recipients for the 2005 prize included six Livermore scientists--physicists Fred Streitz, James Glosli, and Mehul Patel and computer scientists Bor Chan, Robert Yates, and Bronis de Supinski--as well as IBM researchers James Sexton and John Gunnels. This …
Date: February 6, 2007
Creator: Hazi, A U
Object Type: Report
System: The UNT Digital Library
Passenger Rail Security: Federal Strategy and Enhanced Coordination Needed to Prioritize and Guide Security Efforts (open access)

Passenger Rail Security: Federal Strategy and Enhanced Coordination Needed to Prioritize and Guide Security Efforts

Testimony issued by the Government Accountability Office with an abstract that begins "The 2005 London subway bombings and 2006 rail attacks in Mumbai, India highlighted the vulnerability of passenger rail and other surface transportation systems to terrorist attack and demonstrated the need for greater focus on securing these systems. This testimony is based primarily on GAO's September 2005 passenger rail security report and selected program updates obtained in January 2007. Specifically, it addressees (1) the extent to which the Department of Homeland Security (DHS) has assessed the risks facing the U.S. passenger rail system and developed a strategy based on risk assessment for securing all modes of transportation, including passenger rail; (2) the actions that the Transportation Security Administration (TSA) and other federal agencies have taken to enhance the security of the U.S. passenger rail system, improve federal coordination, and develop industry partnerships; and (3) the security practices that domestic and selected foreign passenger rail operators have implemented to enhance security."
Date: February 6, 2007
Creator: United States. Government Accountability Office.
Object Type: Text
System: The UNT Digital Library
A brief survey on climate change effects on the Indian Monsoon (open access)

A brief survey on climate change effects on the Indian Monsoon

Each year, Indian summer monsoon season begins in June and ends in September. Surface winds blow from the southwest during this season. The Indian summer monsoon typically covers large areas of India with western and central India receiving more than 90% of their total annual precipitation during this period, and southern and northwestern India receiving 50%-75% of their total annual rainfall. Overall, monthly totals average 200-300 mm over the country as a whole, with the largest values observed during the heart of the monsoon season in July and August. In all total, India receives about 870 mm of rainfall in a normal summer monsoon season. This summary discusses the effects of climate change on the frequency, mean rainfall, duration and the variability of the Indian Monsoon. East Asian Monsoon in the southeastern part of Asia is not discussed in this summary. Changes in monsoon characteristics are mainly inferred from climate model simulations submitted to the Intergovernmental Panel on Climate Change (IPCC)'s Fourth Assessment Report (AR4). It should be cautioned that there is a large range in the results from these models. For instance, the range of mean monsoon precipitation as simulated by the AR4 models over India is from 500 …
Date: February 6, 2007
Creator: Bala, G.
Object Type: Report
System: The UNT Digital Library
Medicare: FY2008 Budget Issues (open access)

Medicare: FY2008 Budget Issues

This report discusses President's budget request to Congress for Medicare, for the following federal fiscal year, along with projections for the five-year budget window. The President’s 2008 budget includes Medicare legislative proposals with estimated savings of $4.3 billion in 2008 and $65.6 billion over the five-year budget window.
Date: February 6, 2007
Creator: Chaikind, Hinda; Jacobson, Gretchen A.; Hahn, Jim; Morgan, Paulette C.; O'Sullivan, Jennifer & Stockdale, Holly Sue
Object Type: Report
System: The UNT Digital Library
Global Climate Change and Wildlife (open access)

Global Climate Change and Wildlife

This report gives an overview of Global climate change and its effects on wildlife.
Date: February 6, 2007
Creator: Sheikh, Pervaze A.; Corn, M. Lynne; Leggett, Jane A. & Folger, Peter
Object Type: Report
System: The UNT Digital Library
Thermodynamic Properties of Three Pyridine Carboxylic Acid Methyl Ester Isomers (open access)

Thermodynamic Properties of Three Pyridine Carboxylic Acid Methyl Ester Isomers

This article discusses the thermodynamic properties of three pyridine carboxylic acid methyl ester isomers.
Date: February 6, 2007
Creator: Silva, Maria D. M. C. Ribeiro da; Freitas, Vera L. S.; Santos, Luís M. N. B. F.; Fulem, Michal; Sottomayor, M. J.; Monte, Manuel J. S. et al.
Object Type: Article
System: The UNT Digital Library