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AdS/CFT and QCD (open access)

AdS/CFT and QCD

The AdS/CFT correspondence between string theory in AdS space and conformal .eld theories in physical spacetime leads to an analytic, semi-classical model for strongly-coupled QCD which has scale invariance and dimensional counting at short distances and color confinement at large distances. Although QCD is not conformally invariant, one can nevertheless use the mathematical representation of the conformal group in five-dimensional anti-de Sitter space to construct a first approximation to the theory. The AdS/CFT correspondence also provides insights into the inherently non-perturbative aspects of QCD, such as the orbital and radial spectra of hadrons and the form of hadronic wavefunctions. In particular, we show that there is an exact correspondence between the fifth-dimensional coordinate of AdS space z and a specific impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron in ordinary space-time. This connection allows one to compute the analytic form of the frame-independent light-front wavefunctions, the fundamental entities which encode hadron properties and allow the computation of decay constants, form factors, and other exclusive scattering amplitudes. New relativistic lightfront equations in ordinary space-time are found which reproduce the results obtained using the 5-dimensional theory. The effective light-front equations possess remarkable algebraic structures …
Date: February 21, 2007
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
Object Type: Article
System: The UNT Digital Library
The Altus Times (Altus, Okla.), Vol. 108, No. 281, Ed. 1 Wednesday, February 21, 2007 (open access)

The Altus Times (Altus, Okla.), Vol. 108, No. 281, Ed. 1 Wednesday, February 21, 2007

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: February 21, 2007
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Aviation Safety: Improved Data Collection Needed for Effective Oversight of Air Ambulance Industry (open access)

Aviation Safety: Improved Data Collection Needed for Effective Oversight of Air Ambulance Industry

A letter report issued by the Government Accountability Office with an abstract that begins "Air ambulance transport is widely regarded as improving the chances of survival for trauma victims and other critical patients. However, in recent years, the number of air ambulance accidents has led to increased industry scrutiny by government agencies, the public, the media, and the industry itself. The Federal Aviation Administration (FAA), which provides safety oversight, has been called upon by the National Transportation Safety Board (NTSB) and others to issue more stringent safety requirements for the industry. GAO's study addressed (1) recent trends in the air ambulance industry, (2) FAA's challenges in providing safety oversight, and (3) FAA's efforts to address the challenges and what is known about the effects of these efforts. To address these issues, we analyzed FAA, NTSB, and industry data, interviewed federal and industry officials, and conducted five site visits, among other things."
Date: February 21, 2007
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 86, No. 86, Ed. 1 Wednesday, February 21, 2007 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 86, No. 86, Ed. 1 Wednesday, February 21, 2007

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: February 21, 2007
Creator: Clements, Clifford E.
Object Type: Newspaper
System: The Portal to Texas History
Beryllium Health and Safety Committee Data Reporting Task Force (open access)

Beryllium Health and Safety Committee Data Reporting Task Force

On December 8, 1999, the Department of Energy (DOE) published Title 10 CFR 850 (hereafter referred to as the Rule) to establish a chronic beryllium disease prevention program (CBDPP) to: {sm_bullet} reduce the number of workers currently exposed to beryllium in the course of their work at DOE facilities managed by DOE or its contractors, {sm_bullet} minimize the levels of, and potential for, expos exposure to beryllium, and {sm_bullet} establish medical surveillance requirements to ensure early detection of the disease.
Date: February 21, 2007
Creator: MacQueen, D. H.
Object Type: Report
System: The UNT Digital Library
Biotechnology in Animal Agriculture: Status and Current Issues (open access)

Biotechnology in Animal Agriculture: Status and Current Issues

This report provides information about the Status and Current Issues in Biotechnology in Animal Agriculture which has rapid advances.
Date: February 21, 2007
Creator: Becker, Geoffrey S. & Cowan, Tadlock
Object Type: Report
System: The UNT Digital Library
Business Tax Issues in 2007 (open access)

Business Tax Issues in 2007

This report discusses the information related to business tax issues in the year 2007. It also discusses the business tax legislation, 2001-2006.
Date: February 21, 2007
Creator: Brumbaugh, David L.
Object Type: Report
System: The UNT Digital Library
Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 52A, Ed. 1 Wednesday, February 21, 2007 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 52A, Ed. 1 Wednesday, February 21, 2007

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: February 21, 2007
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
The Clifton Record (Clifton, Tex.), Vol. 112, No. 8, Ed. 1 Wednesday, February 21, 2007 (open access)

The Clifton Record (Clifton, Tex.), Vol. 112, No. 8, Ed. 1 Wednesday, February 21, 2007

Weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: February 21, 2007
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
The Collegian (Hurst, Tex.), Vol. 19, No. 18, Ed. 1 Wednesday, February 21, 2007 (open access)

The Collegian (Hurst, Tex.), Vol. 19, No. 18, Ed. 1 Wednesday, February 21, 2007

Weekly student newspaper published in Hurst, Texas serving the Tarrant County College District that includes school news and information along with advertising.
Date: February 21, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Colony Courier-Leader (The Colony, Tex.), Vol. 26, No. 3, Ed. 1 Wednesday, February 21, 2007 (open access)

The Colony Courier-Leader (The Colony, Tex.), Vol. 26, No. 3, Ed. 1 Wednesday, February 21, 2007

Weekly newspaper from The Colony, Texas that includes local, state, and national news along with advertising.
Date: February 21, 2007
Creator: Crimmins, Blaine
Object Type: Newspaper
System: The Portal to Texas History
Diagnostics for the Combustion Science Workbench (open access)

Diagnostics for the Combustion Science Workbench

As the cost of computers declines relative to outfitting andmaintaining laser spectroscopy laboratories, computers will account foran increasing proportion of the research conducted in fundamentalcombustion science. W.C. Gardiner foresaw that progress will be limitedby the ability to understand the implications of what has been computedand to draw inferences about the elementary components of the combustionmodels. Yet the diagnostics that are routinely applied to computerexperiments have changed little from the sensitivity analyses includedwith the original chemkin software distribution. This paper describessome diagnostics capabilities that may be found on the virtual combustionscience workbench of the future. These diagnostics are illustrated bysome new results concerning which of the hydrogen/oxygen chain branchingreactions actually occur in flames, the increased formation of NOx inwrinkled flames versus flat flames, and the adequacy oftheoreticalpredictions of the effects of stretch. Several areas are identified wherework is needed, including the areas of combustion chemistry and laserdiagnostics, to make the virtual laboratory a reality.
Date: February 21, 2007
Creator: Grcar, J. F.; Day, M. S. & Bell, J. B.
Object Type: Article
System: The UNT Digital Library
The Digital Millennium Copyright Act: Exemptions to the Prohibition on Circumvention (open access)

The Digital Millennium Copyright Act: Exemptions to the Prohibition on Circumvention

This report reviews the statutory basis for the triennial exemptions, explains the Copyright Office's rule-making process pursuant to the Digital Millennium Copyright Act (DMCA), summarizes the exemptions granted and rejected in 2006, and describes public reactions to the 2006 exemptions.
Date: February 21, 2007
Creator: Manuel, Kate M. & Yeh, Brian T.
Object Type: Report
System: The UNT Digital Library
Directly Imaging Fast Reaction Fronts (open access)

Directly Imaging Fast Reaction Fronts

Direct observation of fast intermetallic phase formation in Reactive Multilayer Foils (RMLFs) has been achieved. Snap-shots of the reaction appear to show development of mass-thickness contrast of the unmixed Al and Ni layers and an intermetallic phase. Electron imaging of these RMLF reaction fronts have never been attained in the past. The reaction front travels at {approx}10 meters per second as the nanoscale layers mix in an exothermic chain reaction, thus making traditional in situ electron microscopy {approx}10{sup 5} times too slow to produce such an image. The DTEM capability to produce several million electrons within nanoseconds for single-pulse imaging made this experiment possible. Additionally, the sample drive laser ensures reliable experiment initiation and repeatability. In no other way could such a high velocity event be captured at this magnification. RMLF reaction fronts continue to be analyzed via diffraction for complete phase evolution with respect to time. High quality diffraction patterns enable quantitative phase information to be obtained for future comparison to simulation.
Date: February 21, 2007
Creator: Kim, J. S.; LaGrange, T. B.; Reed, B. W.; Campbell, G. H. & Browning, N. D.
Object Type: Report
System: The UNT Digital Library
ELECTRON AVALANCHE MODEL OF DIELECTRIC-VACUUM SURFACE BREAKDOWN (open access)

ELECTRON AVALANCHE MODEL OF DIELECTRIC-VACUUM SURFACE BREAKDOWN

The model assumes that an 'initiating event' results in positive ions on the surface near the anode and reverses the direction of the normal component of electric field so that electrons in vacuum are attracted to the dielectric locally. A sequence of surface electron avalanches progresses in steps from the anode to the cathode. For 200 kV across 1 cm, the spacing of avalanches is predicted to be about 13 microns. The time for avalanches to step from the anode to the cathode is predicted to be about a ns.
Date: February 21, 2007
Creator: Lauer, E J
Object Type: Article
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, February 21, 2007 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, February 21, 2007

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: February 21, 2007
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Final Report: Biological and Synthetic Nanostructures Controlled at the Atomistic Level (open access)

Final Report: Biological and Synthetic Nanostructures Controlled at the Atomistic Level

Nanotechnology holds great promise for many application fields, ranging from the semiconductor industry to medical research and national security. Novel, nanostructured materials are the fundamental building blocks upon which all these future nanotechnologies will be based. In this Strategic Initiative (SI) we conducted a combined theoretical and experimental investigation of the modeling, synthesis, characterization, and design techniques which are required to fabricate semiconducting and metallic nanostructures with enhanced properties. We focused on developing capabilities that have broad applicability to a wide range of materials and can be applied both to nanomaterials that are currently being developed for nanotechnology applications and also to new, yet to be discovered, nanomaterials. During this 3 year SI project we have made excellent scientific progress in each of the components of this project. We have developed first-principles techniques for modeling the structural, electronic, optical, and transport properties of materials at the nanoscale. For the first time, we have simulated nanomaterials both in vacuum and in aqueous solution. These simulation capabilities harness the worldleading computational resources available at LLNL to model, at the quantum mechanical level, systems containing hundreds of atoms and thousands of electrons. Significant advances in the density functional and quantum Monte Carlo techniques …
Date: February 21, 2007
Creator: Williamson, A & van Buuren, T
Object Type: Report
System: The UNT Digital Library
Final Technical Report, Oct 2004 - Nov. 2006, High Performance Flexible Reversible Solid Oxide Fuel Cell (open access)

Final Technical Report, Oct 2004 - Nov. 2006, High Performance Flexible Reversible Solid Oxide Fuel Cell

This report summarizes the work performed for the program entitled “High Performance Flexible Reversible Solid Oxide Fuel Cell” under Cooperative Agreement DE-FC36-04GO14351 for the U. S. Department of Energy. The overall objective of this project is to demonstrate a single modular stack that generates electricity from a variety of fuels (hydrogen and other fuels such as biomass, distributed natural gas, etc.) and when operated in the reverse mode, produces hydrogen from steam. This project has evaluated and selected baseline cell materials, developed a set of materials for oxygen and hydrogen electrodes, and optimized electrode microstructures for reversible solid oxide fuel cells (RSOFCs); and demonstrated the feasibility and operation of a RSOFC multi-cell stack. A 10-cell reversible SOFC stack was operated over 1000 hours alternating between fuel cell (with hydrogen and methane as fuel) and steam electrolysis modes. The stack ran very successfully with high power density of 480 mW/cm2 at 0.7V and 80% fuel utilization in fuel cell mode and >6 SLPM hydrogen production in steam electrolysis mode using about 1.1 kW electrical power. The hydrogen generation is equivalent to a specific capability of 2.59 Nm3/m2 with electrical energy demand of 3 kWh/Nm3. The performance stability in electrolysis mode was …
Date: February 21, 2007
Creator: Guan, Jie & Minh, Nguyen
Object Type: Report
System: The UNT Digital Library
The Goldthwaite Eagle (Goldthwaite, Tex.), Vol. 112, No. 32, Ed. 1 Wednesday, February 21, 2007 (open access)

The Goldthwaite Eagle (Goldthwaite, Tex.), Vol. 112, No. 32, Ed. 1 Wednesday, February 21, 2007

Weekly newspaper from Goldthwaite, Texas that includes local, state, and national news along with extensive advertising.
Date: February 21, 2007
Creator: Bridges, Steven W.
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Dallas, Tex.), Vol. 30, No. 316, Ed. 1 Wednesday, February 21, 2007 (open access)

The Greensheet (Dallas, Tex.), Vol. 30, No. 316, Ed. 1 Wednesday, February 21, 2007

Free weekly newspaper that includes business and classified advertising.
Date: February 21, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 38, No. 28, Ed. 1 Wednesday, February 21, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 28, Ed. 1 Wednesday, February 21, 2007

Free weekly newspaper that includes business and classified advertising.
Date: February 21, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 38, No. 29, Ed. 1 Wednesday, February 21, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 29, Ed. 1 Wednesday, February 21, 2007

Free weekly newspaper that includes business and classified advertising.
Date: February 21, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Greensheet (Houston, Tex.), Vol. 38, No. 30, Ed. 1 Wednesday, February 21, 2007 (open access)

Greensheet (Houston, Tex.), Vol. 38, No. 30, Ed. 1 Wednesday, February 21, 2007

Free weekly newspaper that includes business and classified advertising.
Date: February 21, 2007
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
HEND: A Database for High Energy Nuclear Data (open access)

HEND: A Database for High Energy Nuclear Data

We propose to develop a high-energy heavy-ion experimental database and make it accessible to the scientific community through an on-line interface. The database will be searchable and cross-indexed with relevant publications, including published detector descriptions. It should eventually contain all published data from older heavy-ion programs such as the Bevalac, AGS, SPS and FNAL fixed-target programs, as well as published data from current programs at RHIC and new facilities at GSI (FAIR), KEK/Tsukuba and the LHC collider. This data includes all proton-proton, proton-nucleus to nucleus-nucleus collisions as well as other relevant systems and all measured observables. Such a database would have tremendous scientific payoff as it makes systematic studies easier and allows simpler benchmarking of theoretical models to a broad range of experiments. To enhance the utility of the database, we propose periodic data evaluations and topical reviews. These reviews would provide an alternative and impartial mechanism to resolve discrepancies between published data from rival experiments and between theory and experiment. Since this database will be a community resource, it requires the high-energy nuclear physics community's financial and manpower support.
Date: February 21, 2007
Creator: Brown, David & Vogt, Ramona
Object Type: Article
System: The UNT Digital Library