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Final Report on Research Conducted under Grant DE-FG02-98ER14857 (open access)

Final Report on Research Conducted under Grant DE-FG02-98ER14857

Work in the Carpenter laboratory under the aegis of grant DE-FG02-98ER14857 concerned the formation, properties, and reactions of organic free radicals known or believed to be important in hydrocarbon combustion. Both computational and experimental methods were employed in these studies.
Date: January 28, 2008
Creator: Carpenter, Barry,K. & Davis, H., Floyd
Object Type: Report
System: The UNT Digital Library
Dielectric Wakefield Accelerator Experiments at the SABER Facility (open access)

Dielectric Wakefield Accelerator Experiments at the SABER Facility

Electron bunches with the unparalleled combination of high charge, low emittances, and short time duration, as first produced at the SLAC Final Focus Test Beam (FFTB), are foreseen to be produced at the SABER facility. These types of bunches have enabled wakefield driven accelerating schemes of multi-GV/m in plasmas. In the context of the Dielectric Wakefield Accelerators (DWA) such beams, having rms bunch length as short as 20 um, have been used to drive 100 um and 200 um ID hollow tubes above 20 GV/m surface fields. These FFTB tests enabled the measurement of a breakdown threshold in fused silica (with full data analysis still ongoing) [1]. With the construction and commissioning of the SABER facility at SLAC, new experiments would be made possible to test further aspects of DWAs including materials, tube geometrical variations, direct measurements of the Cerenkov fields, and proof of acceleration in tubes >10 cm in length. This collaboration will investigate breakdown thresholds and accelerating fields in new materials including CVD diamond. Here we describe the experimental plans, beam parameters, simulations, and progress to date as well as future prospects for machines based of DWA structures.
Date: January 28, 2008
Creator: Kanareykin, A.; Thompson, M. C.; Berry, M. K.; Blumenfeld, I.; Decker, F. J.; Hogan, M. J. et al.
Object Type: Article
System: The UNT Digital Library
Compound Nucleus Contributions to the Optical Potential (open access)

Compound Nucleus Contributions to the Optical Potential

An ab-initio calculation of the optical potential for neutron-nucleus scattering has been performed by explicitly coupling the elastic channel to all the particle-hole (p-h) excitation states in the target. These p-h states may be regarded as doorway states through which the flux flows to more complicated configurations, and (in the end) to long-lived compound nucleus resonances. The random-phase approximation (RPA) provides the linear combinations of p-h states that include the residual interactions within the target, and we show preliminary results for elastic flux loss using both p-h and RPA descriptions of target excitations.
Date: January 28, 2008
Creator: Thompson, I J; Dietrich, F S; Escher, J E & Dupuis, M
Object Type: Article
System: The UNT Digital Library
STAR Vertex Detector Upgrade Development (open access)

STAR Vertex Detector Upgrade Development

We report on the development and prototyping efforts undertaken with the goal of producing a micro-vertex detector for the STAR experiment at the RHIC accelerator at BNL. We present the basic detector requirements and show a sensor development path, conceptual mechanical design candidates and readout architecture. Prototyping and beam test results with current generation MimoSTAR-2 sensors and a readout system featuring FPGA based on-the-fly hit finding and data sparsification are also presented.
Date: January 28, 2008
Creator: Greiner, Leo C.; Matis, Howard S.; Stezelberger, Thorsten; Vu,Chinh Q.; Wieman, Howard; Szelezniak, Michal et al.
Object Type: Article
System: The UNT Digital Library
Quantitive DNA Fiber Mapping (open access)

Quantitive DNA Fiber Mapping

Several hybridization-based methods used to delineate single copy or repeated DNA sequences in larger genomic intervals take advantage of the increased resolution and sensitivity of free chromatin, i.e., chromatin released from interphase cell nuclei. Quantitative DNA fiber mapping (QDFM) differs from the majority of these methods in that it applies FISH to purified, clonal DNA molecules which have been bound with at least one end to a solid substrate. The DNA molecules are then stretched by the action of a receding meniscus at the water-air interface resulting in DNA molecules stretched homogeneously to about 2.3 kb/{micro}m. When non-isotopically, multicolor-labeled probes are hybridized to these stretched DNA fibers, their respective binding sites are visualized in the fluorescence microscope, their relative distance can be measured and converted into kilobase pairs (kb). The QDFM technique has found useful applications ranging from the detection and delineation of deletions or overlap between linked clones to the construction of high-resolution physical maps to studies of stalled DNA replication and transcription.
Date: January 28, 2008
Creator: Lu, Chun-Mei; Wang, Mei; Greulich-Bode, Karin M.; Weier, Jingly F. & Weier, Heinz-Ulli G.
Object Type: Book
System: The UNT Digital Library
EVAPORITE MICROBIAL FILMS, MATS, MICROBIALITES AND STROMATOLITES (open access)

EVAPORITE MICROBIAL FILMS, MATS, MICROBIALITES AND STROMATOLITES

Evaporitic environments are found in a variety of depositional environments as early as the Archean. The depositional settings, microbial community and mineralogical composition vary significantly as no two settings are identical. The common thread linking all of the settings is that evaporation exceeds precipitation resulting in elevated concentrations of cations and anions that are higher than in oceanic systems. The Dead Sea and Storrs Lake are examples of two diverse modern evaporitic settings as the former is below sea level and the latter is a coastal lake on an island in the Caribbean. Each system varies in water chemistry as the Dead Sea dissolved ions originate from surface weathered materials, springs, and aquifers while Storrs Lake dissolved ion concentration is primarily derived from sea water. Consequently some of the ions, i.e., Sr, Ba are found at significantly lower concentrations in Storrs Lake than in the Dead Sea. The origin of the dissolved ions are ultimately responsible for the pH of each system, alkaline versus mildly acidic. Each system exhibits unique biogeochemical properties as the extreme environments select certain microorganisms. Storrs Lake possesses significant biofilms and stromatolitic deposits and the alkalinity varies depending on rainfall and storm activity. The microbial community …
Date: January 28, 2008
Creator: Brigmon, R; Penny Morris, P & Garriet Smith, G
Object Type: Book
System: The UNT Digital Library
Foot & Mouth Disease & Ulcerative/Vesicular Rule-outs: Challenges Encountered in Recent Outbreaks (open access)

Foot & Mouth Disease & Ulcerative/Vesicular Rule-outs: Challenges Encountered in Recent Outbreaks

Foot and mouth disease (FMD) is a highly infectious and contagious viral disease affecting bovidae (cattle, zebus, domestic buffaloes, yaks), sheep, goats, swine, all wild ruminants and suidae. Camelidae (camels, dromedaries, llamas, vicunas) have low susceptibility. Foot and mouth disease is caused by a RNS virus of the family Picornaviridae, genus Aphthovirus. There are seven immunologically distinct serotypes: A, O, C, SAT1, SAT2, SAT3, Asia 1. Foot and mouth disease causes significant economic loss both to countries who manage it as an endemic disease (with or without vaccination), as well as those FMD free countries which may become infected. The mortality rate is low in adult animals, but often higher in young due to myocarditis. Foot and mouth disease is endemic in parts of Asia, Africa, the Middle East and South America (sporadic outbreaks in free areas). The Office of International Epizootics (OIE), also referred to the World Organization for Animal Health maintains an official list of free countries and zones.1 The OIE Terrestrial Code (Chapter 2.2.10) provides detailed information on the categories of freedom that can be allocated to a country as well as guidelines for the surveillance for foot and mouth disease (Appendix 3.8.7). In short, countries may …
Date: January 28, 2008
Creator: Hullinger, P
Object Type: Article
System: The UNT Digital Library
EMSL Quarterly Highlights Report: 1st Quarter, FY08 (open access)

EMSL Quarterly Highlights Report: 1st Quarter, FY08

The EMSL Quarterly Highlights Report covers the science, staff and user recognition, and publication activities that occurred during the 1st quarter (October 2007 - December 2007) of Fiscal Year 2008.
Date: January 28, 2008
Creator: Showalter, Mary Ann
Object Type: Report
System: The UNT Digital Library
On the Possibility of Accelerating Positron on an Electron Wake at SABER (open access)

On the Possibility of Accelerating Positron on an Electron Wake at SABER

A new approach for positron acceleration in non-linear plasma wakefields driven by electron beams is presented. Positrons can be produced by colliding an electron beam with a thin foil target embedded in the plasma. Integration of positron production and acceleration in one stage is realized by a single relativistic, intense electron beam. Simulations with the parameters of the proposed SABER facility [1] at SLAC suggest that this concept could be tested there.
Date: January 28, 2008
Creator: Ischebeck, R.; Joshi, C.; Katsouleas, T. C.; Muggli, P. & Wang, X.
Object Type: Article
System: The UNT Digital Library
Correlating Pulses from Two Spitfire, 800nm Lasers (open access)

Correlating Pulses from Two Spitfire, 800nm Lasers

The E163 laser acceleration experiments conducted at SLAC have stringent requirements on the temporal properties of two regeneratively amplified, 800nm, Spitfire laser systems. To determine the magnitude and cause of timing instabilities between the two Ti:Sapphire amplifiers, we pass the two beams through a cross-correlator and focus the combined beam onto a Hamamatsu G1117 photodiode. The photodiode has a bandgap such that single photon processes are suppressed and only the second order, two-photon process produces an observable response. The response is proportional to the square of the intensity. The diode is also useful as a diagnostic to determine the optimal configuration of the compression cavity.
Date: January 28, 2008
Creator: Colby, Eric R.; Mcguinness, C.; Zacherl, W. D. & Plettner, T.
Object Type: Article
System: The UNT Digital Library
New Fragment Separation Technology for Superheavy Element Research (open access)

New Fragment Separation Technology for Superheavy Element Research

This project consisted of three major research areas: (1) development of a solid Pu ceramic target for the MASHA separator, (2) chemical separation of nuclear decay products, and (3) production of new isotopes and elements through nuclear reactions. There have been 16 publications as a result of this project, and this collection of papers summarizes our accomplishments in each of the three areas of research listed above. The MASHA (Mass Analyzer for Super-Heavy Atoms) separator is being constructed at the U400 Cyclotron at the Flerov Laboratory of Nuclear Reactions in Dubna, Russia. The purpose of the separator is to physically separate the products from nuclear reactions based on their isotopic masses rather than their decay characteristics. The separator was designed to have a separation between isotopic masses of {+-}0.25 amu, which would enable the mass of element 114 isotopes to be measured with outstanding resolution, thereby confirming their discovery. In order to increase the production rate of element 114 nuclides produced via the {sup 244}Pu+{sup 48}Ca reaction, a new target technology was required. Instead of a traditional thin actinide target, the MASHA separator required a thick, ceramic-based Pu target that was thick enough to increase element 114 production while still …
Date: January 28, 2008
Creator: Shaughnessy, D A; Moody, K J; Henderson, R A; Kenneally, J M; Landrum, J H; Lougheed, R W et al.
Object Type: Report
System: The UNT Digital Library
U.S. Global Climate Change Policy: Evolving Views on Cost, Competitiveness, and Comprehensiveness (open access)

U.S. Global Climate Change Policy: Evolving Views on Cost, Competitiveness, and Comprehensiveness

This report discusses the evolving views on cost, competitiveness, and comprehensiveness regarding the U.S. global climate change policy. The report starts out with the U.N. Framework Convention on Climate Change (UNFCCC). It discusses the Energy Policy Act of 1992 (EPACT), and negotiations on the Kyoto Protocol, which established mandatory limits on emissions for developed countries.
Date: January 28, 2008
Creator: Parker, Larry B. & Blodgett, John E.
Object Type: Report
System: The UNT Digital Library
Air Quality Issues and Animal Agriculture: A Primer (open access)

Air Quality Issues and Animal Agriculture: A Primer

This report reviews the types of air emissions from livestock and poultry operations and their human health and environmental impacts. It then discusses provisions of several federal laws concerned with environmental impacts, beginning with the Clean Water Act, because protecting water resources has been the primary regulatory focus regarding livestock and animal operations.
Date: January 28, 2008
Creator: Copeland, Claudia
Object Type: Report
System: The UNT Digital Library
Nuclear Energy Policy (open access)

Nuclear Energy Policy

This report discusses the nuclear energy policy issues facing Congress that include the implementation of federal incentives for new commercial reactors, radioactive waste management policy, research and development priorities, power plant safety and regulation, nuclear weapons proliferation, and security against terrorist attacks.
Date: January 28, 2008
Creator: Holt, Mark
Object Type: Report
System: The UNT Digital Library
Gray Wolves Under the Endangered Species Act: Distinct Population Segments and Experimental Populations (open access)

Gray Wolves Under the Endangered Species Act: Distinct Population Segments and Experimental Populations

This report looks at the distinct population segments (DPS) process as it is applied to the gray wolf. It also reviews experimental populations of wolves under the ESA and their protections.
Date: January 28, 2008
Creator: Alexander, Kristina & Corn, M. L.
Object Type: Report
System: The UNT Digital Library
Should Credit Unions Be Taxed? (open access)

Should Credit Unions Be Taxed?

None
Date: January 28, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Open Source Intelligence (OSINT): Issues for Congress (open access)

Open Source Intelligence (OSINT): Issues for Congress

None
Date: January 28, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
U.S. Embassy in Iraq (open access)

U.S. Embassy in Iraq

This report discusses the establishment and the role of the U.S. embassy in Iraq.
Date: January 28, 2008
Creator: Epstein, Susan B.
Object Type: Report
System: The UNT Digital Library
Paraprofessional Quality and the No Child Left Behind Act of 2001 (open access)

Paraprofessional Quality and the No Child Left Behind Act of 2001

None
Date: January 28, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
State and Local Restrictions on Employing, Renting Property to, or Providing Services for Unauthorized Aliens: Legal Issues and Recent Judicial Developments (open access)

State and Local Restrictions on Employing, Renting Property to, or Providing Services for Unauthorized Aliens: Legal Issues and Recent Judicial Developments

This report discusses the constitutional issues raised in relation to state and local laws intended to deter the presence of unauthorized aliens, along with the implications that federal civil rights statutes might have on the implementation and enforcement of measures restricting such persons' ability to obtain employment, housing, or other state and local benefits or services.
Date: January 28, 2008
Creator: Garcia, Michael John; Feder, Jody & Smith, Alison M.
Object Type: Report
System: The UNT Digital Library
U.S.-EU Cooperation Against Terrorism (open access)

U.S.-EU Cooperation Against Terrorism

None
Date: January 28, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Loan Forgiveness for Public Service Employees Under the William D. Ford Direct Loan Program (open access)

Loan Forgiveness for Public Service Employees Under the William D. Ford Direct Loan Program

The College Cost Reduction and Access Act of 2007 (CCRAA; P.L. 110-84) establishes a new loan forgiveness provision for borrowers of loans made under the William D. Ford Direct Loan (DL) program who are employed in public service jobs for 10 years during the repayment of their loans. This report provides a brief description of the DL program loan forgiveness provision for public service employees and identifies issues that may be addressed as it is implemented.
Date: January 28, 2008
Creator: Smole, David P.
Object Type: Report
System: The UNT Digital Library
Agricultural Biotechnology: The U.S.-EU Dispute (open access)

Agricultural Biotechnology: The U.S.-EU Dispute

This report focuses on a conflict between the European Union (EU) and the United States, Canada, and Argentina. The United States suggests that the European Union's moratorium costs the U.S. 300 million dollars in exports to the EU annually. Moreover, the report highlights other concerns the U.S. has with the EU's biotechnology policies.
Date: January 28, 2008
Creator: Hanrahan, Charles E.
Object Type: Report
System: The UNT Digital Library
U.S. Arms Sales to Pakistan (open access)

U.S. Arms Sales to Pakistan

None
Date: January 28, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library