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Dynamic molecular imaging of cardiac innervation using a dual headpinhole SPECT system (open access)

Dynamic molecular imaging of cardiac innervation using a dual headpinhole SPECT system

Typically 123I-MIBG is used for the study of innervation andfunction of the sympathetic nervous system in heart failure. The protocolinvolves two studies: first a planar or SPECT scan is performed tomeasure initial uptake of the tracer, followed some 3-4 hours later byanother study measuring the wash-out of the tracer from the heart. A fastwash-out is indicative of a compromised heart. In this work, a dual headpinhole SPECT system was used for imaging the distribution and kineticsof 123I-MIBG in the myocardium of spontaneous hypertensive rats (SHR) andnormotensive Wistar Kyoto (WKY) rats. The system geometry was calibratedbased on a nonlinear point projection fitting method using a three-pointsource phantom. The angle variation effect of the parameters was modeledwith a sinusoidal function. A dynamic acquisition was performed byinjecting 123I-MIBG into rats immediately after starting the dataacquisition. The detectors rotated continuously performing a 360o dataacquisition every 90 seconds. We applied the factor analysis (FA)methodand region of interest (ROI) sampling method to obtain time activitycurves (TACs)in the blood pool and myocardium and then appliedtwo-compartment modeling to estimate the kinetic parameters. Since theinitial injection bolus is too fast for obtaining a consistenttomographic data set in the first few minutes of the study, we appliedthe FA method directly …
Date: March 29, 2008
Creator: Hu, Jicun; Boutchko, Rostyslav; Sitek, Arkadiusz; Reutter, BryanW.; Huesman, Ronald H. & Gullberg, Grant T.
System: The UNT Digital Library
Recent Advances on Hydrogenic Retention in ITER's Plasma-Facing Materials: BE, C, W. (open access)

Recent Advances on Hydrogenic Retention in ITER's Plasma-Facing Materials: BE, C, W.

Management of tritium inventory remains one of the grand challenges in the development of fusion energy and the choice of plasma-facing materials is a key factor for in-vessel tritium retention. The Atomic and Molecular Data Unit of the International Atomic Energy Agency organized a Coordinated Research Project (CRP) on the overall topic of tritium inventory in fusion reactors during the period 2001-2006. This dealt with hydrogenic retention in ITER's plasma-facing materials, Be, C, W, and in compounds (mixed materials) of these elements as well as tritium removal techniques. The results of the CRP are summarized in this article together with recommendations for ITER. Basic parameters of diffusivity, solubility and trapping in Be, C and W are reviewed. For Be, the development of open porosity can account for transient hydrogenic pumping but long term retention will be dominated by codeposition. Codeposition is also the dominant retention mechanism for carbon and remains a serious concern for both Be and C containing layers. Hydrogenic trapping in unirradiated tungsten is low but will increase with ion and neutron damage. Mixed materials will be formed in a tokamak and these can also retain significant amounts of hydrogen isotopes. Oxidative and photon-based techniques for detritiation of …
Date: March 29, 2008
Creator: Skinner, C H; Alimov, Kh; Bekris, N; Causey, R A; Clark, R.E.H.; Coad, J P et al.
System: The UNT Digital Library
Avian Influenza in Poultry and Wild Birds (open access)

Avian Influenza in Poultry and Wild Birds

This report is categorized into six categories: (I) What is Avian Influenza?, (II) Status of Avian Influenza Outbreaks, (III) Transmission, (IV) Control, (V) Economic Impacts, and (VI) Legislative Actions.
Date: March 29, 2007
Creator: Monke, Jim
System: The UNT Digital Library
Carbon Sequestration in Forests (open access)

Carbon Sequestration in Forests

This report provides an overview of the congressional interests in carbon sequestration.
Date: March 29, 2007
Creator: Gorte, Ross W.
System: The UNT Digital Library
Climate Change: Greenhouse Gas Reduction Bills in the 110th Congress (open access)

Climate Change: Greenhouse Gas Reduction Bills in the 110th Congress

This report presents a side-by-side comparison of the major provisions of the 1990 Clean Air Act Amendments, and includes a glossary of common terms.
Date: March 29, 2007
Creator: Parker, Larry & Yacobucci, Brent D.
System: The UNT Digital Library
Dynamic Data-Driven Event Reconstruction for Atmospheric Releases (open access)

Dynamic Data-Driven Event Reconstruction for Atmospheric Releases

Accidental or terrorist releases of hazardous materials into the atmosphere can impact large populations and cause significant loss of life or property damage. Plume predictions have been shown to be extremely valuable in guiding an effective and timely response. The two greatest sources of uncertainty in the prediction of the consequences of hazardous atmospheric releases result from poorly characterized source terms and lack of knowledge about the state of the atmosphere as reflected in the available meteorological data. We have developed a new event reconstruction methodology that provides probabilistic source term estimates from field measurement data for both accidental and clandestine releases. Accurate plume dispersion prediction requires the following questions to be answered: What was released? When was it released? How much material was released? Where was it released? We have developed a dynamic-data-driven event reconstruction capability that couples data and predictive methods through Bayesian inference to obtain a solution to this inverse problem. The solution consists of a probability distribution of unknown source term parameters. For consequence assessment, we then use this probability distribution to construct a 'composite' forward plume prediction that accounts for the uncertainties in the source term. Since in most cases of practical significance it is …
Date: March 29, 2007
Creator: Mirin, A. A. & Kosovic, B.
System: The UNT Digital Library
Egypt: Background and U.S. Relations (open access)

Egypt: Background and U.S. Relations

This report provides an overview of Egyptian politics and current issues in U.S.- Egyptian relations. It briefly provides a political history of modern Egypt, an overview of its political institutions, and a discussion of the prospects for democratization in Egypt. U.S.-Egyptian relations are complex and multi-faceted, and this report addresses the following current topics: the Arab-Israeli peace process, Iraq, terrorism, democratization and reform, human rights, trade, and military cooperation.
Date: March 29, 2007
Creator: Sharp, Jeremy M.
System: The UNT Digital Library
Estate Tax Legislation in the 109th Congress (open access)

Estate Tax Legislation in the 109th Congress

None
Date: March 29, 2007
Creator: Noto, Nonna A.
System: The UNT Digital Library
Farm Commodity Policy: Programs and Issues for Congress (open access)

Farm Commodity Policy: Programs and Issues for Congress

This report summarizes the subsidies that are available for about 25 agricultural commodities representing about one-third of gross farm sales.
Date: March 29, 2007
Creator: Monke, Jim
System: The UNT Digital Library
Financial Market Preparedness: Significant Progress Has Been Made, but Pandemic Planning and Other Challenges Remain (open access)

Financial Market Preparedness: Significant Progress Has Been Made, but Pandemic Planning and Other Challenges Remain

A letter report issued by the Government Accountability Office with an abstract that begins "This is GAO's third report since the September 11 terrorist attacks that assesses progress that market participants and regulators have made to ensure the security and resiliency of our securities markets. This report examined (1) actions taken to improve the markets' capabilities to prevent and recover from attacks; (2) actions taken to improve disaster response and increase telecommunications resiliency; and (3) financial regulators' efforts to ensure market resiliency. GAO inspected physical and electronic security measures and business continuity capabilities using regulatory, government, and industry-established criteria and discussed improvement efforts with broker dealers, banks, regulators, telecommunications carriers, and trade associations."
Date: March 29, 2007
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
The Group of Eight Summits: Evolution and Possible Reform (open access)

The Group of Eight Summits: Evolution and Possible Reform

This report discusses the evolution of the G8 and possible reform as background for the meeting
Date: March 29, 2007
Creator: Weiss, Martin
System: The UNT Digital Library
HYDROGEN INITIATIVE: AN INTEGRATED APPROACH TOWARD RATIONAL NANOCATALYST DESIGN FOR HYDROGEN PRODUCTION. Technical Report-Year 1 (open access)

HYDROGEN INITIATIVE: AN INTEGRATED APPROACH TOWARD RATIONAL NANOCATALYST DESIGN FOR HYDROGEN PRODUCTION. Technical Report-Year 1

The overall objective of this grant is to develop a rational framework for the discovery of low cost, robust, and active nano-catalysts that will enable efficient hydrogen production. Our approach will be the first demonstration of integrated multiscale model, nano-catalyst synthesis, and nanoscale characterization assisted high throughput experimentation (HTE). We will initially demonstrate our approach with ammonia decomposition on noble metal catalysts. Our research focuses on many elements of the Hydrogen Initiative in the Focus Area of “Design of Catalysts at the Nanoscale’. It combines high-throughput screening methods with various nanostructure synthesis protocols, advanced measurements, novel in situ and ex situ characterization techniques, and multiscale theory, modeling and simulation. This project directly addresses several of the long-term goals of the DOE/BES program. In particular, new nanoscale catalytic materials will be synthesized, characterized and modeled for the production of hydrogen from ammonia and a computational framework will be developed for efficient extraction of information from experimental data and for rational design of catalysts whose impact goes well beyond the proposed hydrogen production project. In the first year of the grant, we have carried out HTE screening using a 16 parallel microreactor coupled with an FTIR analysis system. We screened nearly twenty …
Date: March 29, 2007
Creator: Vlachos, Dionisios G; Buttrey, Douglas J & Lauterbach, Jochen
System: The UNT Digital Library
Military Support to the Severely Disabled: Overview of Service Programs (open access)

Military Support to the Severely Disabled: Overview of Service Programs

The Department of Defense (DOD) and each of the military services have established new programs to care for the severely disabled, ensuring rehabilitative assistance and easing the transition back to civilian life. Congress has followed these initiatives with interest and recently directed DOD to develop policies and procedures to standardize these programs. This report examines the background for the new initiatives and provides a status of each program, including contact information.
Date: March 29, 2007
Creator: Henning, Charles A.
System: The UNT Digital Library
On-Line Oxidation of Volatile Organic Compounds Generated by Sawmill Wood Kilns (open access)

On-Line Oxidation of Volatile Organic Compounds Generated by Sawmill Wood Kilns

The primary purpose of this project was to evaluate the effectiveness of the use of hydrogen peroxide in combination with ultra-violet (UV) light for the reduction in the amount of volatile organic compounds (VOC’s) released into the environment during wood drying in sawmill kilns. As originally envisioned the scope of work included the optimization of reaction parameters i.e. pH, peroxide concentration, UV light intensity that would lead to successful destruction of VOC’s. The second phase involved development of a prototypical reactor that could be taken to a sawmill kiln for demonstration of treatment of a slipstream. However, after some of our initial experiments, we were forced to limit ourselves to more modest testing and development. During the project period we designed and constructed a small-scale reactor that was connected to the off-gas from a small wood drying kiln located at the Forest Products Lab at Mississippi State University. We ran a number of tests where we varied the process parameters (peroxide concentration, pH and UV light intensity) with no reasonable amount of VOC destruction. We employed a number of ways to atomize the peroxide into the kiln off-gas including using Laskin nozzles to see if that would improve the VOC …
Date: March 29, 2007
Creator: Kumar, R. Arun; Steele, Philip & Patterson, W. Dean
System: The UNT Digital Library
POTENTIAL IMPACT OF BLENDING RESIDUAL SOLIDS FROM TANKS 18/19 MOUNDS WITH TANK 7 OPERATIONS (open access)

POTENTIAL IMPACT OF BLENDING RESIDUAL SOLIDS FROM TANKS 18/19 MOUNDS WITH TANK 7 OPERATIONS

High level waste tanks 18F and 19F have residual mounds of waste which may require removal before the tanks can be closed. Conventional slurry pump technology, previously used for waste removal and tank cleaning, has been incapable of removing theses mounds from tanks 18F and 19F. A mechanical cleaning method has been identified that is potentially capable of removing and transferring the mound material to tank 7F for incorporation in a sludge batch for eventual disposal in high level waste glass by the Defense Waste Processing Facility. The Savannah River National Laboratory has been requested to evaluate whether the material transferred from tanks 18F/19F by the mechanical cleaning technology can later be suspended in Tank 7F by conventional slurry pumps after mixing with high level waste sludge. The proposed mechanical cleaning process for removing the waste mounds from tanks 18 and 19 may utilize a high pressure water jet-eductor that creates a vacuum to mobilize solids. The high pressure jet is also used to transport the suspended solids. The jet-eductor system will be mounted on a mechanical crawler for movement around the bottom of tanks 18 and 19. Based on physical chemical property testing of the jet-eductor system processed IE-95 …
Date: March 29, 2007
Creator: Eibling, R; Erich Hansen, E & Bradley Pickenheim, B
System: The UNT Digital Library
Salaries of Members of Congress: A List of Payable Rates and Effective Dates, 1789-2007 (open access)

Salaries of Members of Congress: A List of Payable Rates and Effective Dates, 1789-2007

None
Date: March 29, 2007
Creator: unknown
System: The UNT Digital Library
Science & Technology Review May 2007 (open access)

Science & Technology Review May 2007

None
Date: March 29, 2007
Creator: Radousky, H. B.
System: The UNT Digital Library
Advances in Electromagnetic Modelling through High Performance Computing (open access)

Advances in Electromagnetic Modelling through High Performance Computing

Under the DOE SciDAC project on Accelerator Science and Technology, a suite of electromagnetic codes has been under development at SLAC that are based on unstructured grids for higher accuracy, and use parallel processing to enable large-scale simulation. The new modeling capability is supported by SciDAC collaborations on meshing, solvers, refinement, optimization and visualization. These advances in computational science are described and the application of the parallel eigensolver Omega3P to the cavity design for the International Linear Collider is discussed.
Date: March 29, 2006
Creator: Ko, K.; Folwell, N.; Ge, L.; Guetz, A.; Lee, L.; Li, Z. et al.
System: The UNT Digital Library
Argonne National Laboratory Summary Site Environmental Report for Calendar Year 2004. (open access)

Argonne National Laboratory Summary Site Environmental Report for Calendar Year 2004.

This report talks about Argonne National Laboratory summary site environmental report for calendar year 2004
Date: March 29, 2006
Creator: Golchert, N. W.
System: The UNT Digital Library
Association Sponsored Health Plans: Legislation in the 109th Congress (open access)

Association Sponsored Health Plans: Legislation in the 109th Congress

This report describes H.R. 525/S. 406 and S. 1955 which focus on assisting small employers with offering health insurance to their workers.
Date: March 29, 2006
Creator: Hearne, Jean
System: The UNT Digital Library
Beam Losses in the Extraction Line of a TeV E+ E- Linear Collider With a 20-Mrad Crossing Angle (open access)

Beam Losses in the Extraction Line of a TeV E+ E- Linear Collider With a 20-Mrad Crossing Angle

In this paper, we perform a detailed study of the power losses along the postcollision extraction line of a TeV e+e- collider with a crossing angle of 20 mrad between the beams at the interaction point. Five cases are considered here: four luminosity configurations for ILC and one for CLIC. For all of them, the strong beam-beam effects at the interaction point lead to an emittance growth for the outgoing beams, as well as to the production of beamstrahlung photons and e+e- pairs. The power losses along the 20 mrad extraction line, which are due to energy deposition by a fraction of the disrupted beam, of the beamstrahlung photons and of the e+e- coherent pairs, were estimated in the case of ideal collisions, as well as with a vertical position or angular o set at the interaction point.
Date: March 29, 2006
Creator: Ferrari, A.; U., /Uppsala & Nosochkov, Y.
System: The UNT Digital Library
Borehole Data Package for One CY 2005 CERCLA Well 699-S20-E10, 300-FF-5 Operable Unit, Hanford Site, Washington (open access)

Borehole Data Package for One CY 2005 CERCLA Well 699-S20-E10, 300-FF-5 Operable Unit, Hanford Site, Washington

This report supplies the information obtained during drilling, characterization, and installation of the new groundwater monitoring well. This document also provides a compilation of hydrogeologic and well construction information obtained during drilling, well development, and sample collection/analysis activities.
Date: March 29, 2006
Creator: Williams, Bruce A.; Bjornstad, Bruce N.; Lanigan, David C.; Keller, Jason M. & Rockhold, Mark L.
System: The UNT Digital Library
Central Asia: Regional Developments and Implication for U.S. Interests (open access)

Central Asia: Regional Developments and Implication for U.S. Interests

This report provides an overview of U.S. policy concerns regarding countries in central Asia. The report discusses issues such as Fostering Pro-Western Orientations, Obstacles to Peace and Independence, Democratization and Human Rights, Security and Arms Control, Trade and Investment, and provides an Aid Overview.
Date: March 29, 2006
Creator: Nichol, Jim
System: The UNT Digital Library