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Plan Colombia: Drug Reduction Goals Were Not Fully Met, but Security Has Improved; U.S. Agencies Need More Detailed Plans for Reducing Assistance (open access)

Plan Colombia: Drug Reduction Goals Were Not Fully Met, but Security Has Improved; U.S. Agencies Need More Detailed Plans for Reducing Assistance

A letter report issued by the Government Accountability Office with an abstract that begins "In September 1999, the government of Colombia announced a strategy, known as "Plan Colombia," to (1) reduce the production of illicit drugs (primarily cocaine) by 50 percent in 6 years and (2) improve security in Colombia by re-claiming control of areas held by illegal armed groups. Since fiscal year 2000, the United States has provided over $6 billion to support Plan Colombia. The Departments of State, Defense, and Justice and the U.S. Agency for International Development (USAID) manage the assistance. GAO examined (1) the progress made toward Plan Colombia's drug reduction and enhanced security objectives, (2) the results of U.S. aid for the military and police, (3) the results of U.S. aid for non-military programs, and (4) the status of efforts to "nationalize" or transfer operations and funding responsibilities for U.S.-supported programs to Colombia."
Date: October 6, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Top Jets at the LHC (open access)

Top Jets at the LHC

We investigatethe reconstruction of high pT hadronically-decaying top quarksat the Large Hadron Collider. One of the main challenges in identifying energetictop quarks is that the decay products become increasingly collimated. This reducesthe efficacy of conventional reconstruction methods that exploit the topology of thetop quark decay chain. We focus on the cases where the decay products of the topquark are reconstructed as a single jet, a"top-jet." The most basic"top-tag" methodbased on jet mass measurement is considered in detail. To analyze the feasibility ofthe top-tagging method, both theoretical and experimental aspects of the large QCDjet background contribution are examined. Based on a factorization approach, wederive a simple analytic approximation for the shape of the QCD jet mass spectrum.We observe very good agreement with the Monte Carlo simulation. We consider high pT tt bar production in the Standard Model as an example, and show that our theoretical QCD jet mass distributions can efficiently characterize the background via sideband analyses. We show that with 25 fb-1 of data, our approach allows us to resolve top-jets with pT _> 1 TeV, from the QCD background, and about 1.5 TeV top-jets with 100 fb-1, without relying on b-tagging. To further improve the significancewe consider jet shapes …
Date: October 6, 2008
Creator: Almeida, L.G.; Lee, S.J.; Perez, G.; Sung, I. & Virzi, J.
Object Type: Article
System: The UNT Digital Library
Effect of various errors on the Spin Tune and Stable Spin Axis (open access)

Effect of various errors on the Spin Tune and Stable Spin Axis

Even though RHIC has two full Siberian snakes in each ring, there are various perturbations to the ideal case including orbit errors at the snakes, experiment solenoids, injection bumps, and interlaced horizontal-vertical bumps at the hydrogen jet polarimeter. These errors can cause depolarization by shifting the spin tune and tilting the stable spin direction away from vertical. Tilting of the stable spin axis can enhance horizontal depolarizing resonances. This paper presents preliminary results for some of these error scenarios, as well as their impact on the stable spin directions at STAR and PHENIX.
Date: October 6, 2008
Creator: MacKay, W. W.
Object Type: Article
System: The UNT Digital Library
CIBS Solar Cell Development (open access)

CIBS Solar Cell Development

This research focused on efforts to prepare and characterize the first copper-indium-boron-diselenide (CIBS) photovoltaic materials. Attempts to fabricate CIBS in thin-film form followed a three-step process: 1) RF sputtering of copper, indium, and boron to form a copper-indium-boron (CIB) alloy; 2) ex-situ selenization of CIB via physical vapor deposition; 3) annealing the final product. No CIBS materials were produced with this method due to the formation of an unstable boron diselenide species that formed in step 2. Detailed investigations of the CIB alloy formation revealed that boron does not adequately mix with the copper and indium in step 1. In the last year, a nanoscience-based method has shown greater promise for successful CIBS preparation. In this two-step method, sources of copper, indium, boron, and selenium are combined and heated in a high-boiling amine solvent. The isolated product is then annealed at temperatures between 400-500 deg. C. Currently, purified CIBS has not been isolated and characterized but further study and development of this nanoscience-based method is in progress through the support of two grants from the DOE Office of Energy Renewability and Efficiency and the State of Nebraska’s Nebraska Research Initiative program. The research described in this report resulted in four …
Date: October 6, 2008
Creator: Exstrom, Christopher L.
Object Type: Report
System: The UNT Digital Library
Radiative Leptonic B Decays (open access)

Radiative Leptonic B Decays

We present the results of a search for B{sup +} meson decays into {gamma}{ell}{sup +}{nu}{sub {ell}}, where {ell} = e,{mu}. We use a sample of 232 million B{bar B} meson pairs recorded at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II B factory. We measure a partial branching fraction {Delta}{beta} in a restricted region of phase space that reduces the effect of theoretical uncertainties, requiring the lepton energy to be in the range 1.875 and 2.850 GeV, the photon energy to be in the range 0.45 and 2.35 GeV, and the cosine of the angle between the lepton and photon momenta to be less than -0.36, with all quantities computed in the {Upsilon}(4S) center-of-mass frame. We find {Delta}{Beta}(B{sup +} {yields} {gamma}{ell}{sup +}{nu}{sub {ell}}) = (-0.3{sub 1.5}{sup +1.3}(statistical){sub -0.6}{sup +0.6}(systematic) {+-} 0.1(theoretical)) x 10{sup -6}, under the assumption of lepton universality. Interpreted as a 90% confidence-level Bayesian upper limit, the result corresponds to 1.7 x 10{sup -6} for a prior at in amplitude, and 2.3 x 10{sup -6} for a prior at in branching fraction.
Date: October 6, 2008
Creator: Chen, Edward Tann & /Caltech
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Texas Attorney General Opinion: GA-0668 (open access)

Texas Attorney General Opinion: GA-0668

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification; Whether certain posted agenda items satisfy the notice requirements of the Open Meetings Act, chapter 551, Government Code (RQ-0696-GA)
Date: October 6, 2008
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History
The Debt Limit: History and Recent Increases (open access)

The Debt Limit: History and Recent Increases

This report contains the history and increases of the debt limit for the second time in 2008.
Date: October 6, 2008
Creator: Austin, D. Andrew & Levit, Mindy R.
Object Type: Report
System: The UNT Digital Library
QCD Corrections in Transversely Polarized Scattering (open access)

QCD Corrections in Transversely Polarized Scattering

We discuss two recent calculations of higher-order QeD corrections to scattering of transversely polarized hadrons. A basic concept underlying much of the theoretical description of high-energy hadronic scattering is the factorization theorem, which states that large momentum-transfer reactions may be factorized into long-distance pieces that contain information on the structure of the nucleon in terms of its parton densities, and parts that are short-distance and describe the hard interactions of the partons. Two crucial points are that on the one hand the long-distance contributions are universal, i.e., they are the same in any inelastic reaction under consideration, and that on the other hand the short-distance pieces depend only on the large scales related to the large momentum transfer in the overall reaction and, therefore, may be evaluated using QCD perturbation theory. The lowest order for the latter can generally only serve to give a rough description of the reaction under study. It merely captures the main features, but does not usually provide a quantitative understanding. The first-order ('next-to-leading order' (NLO)) corrections are generally indispensable in order to arrive at a firmer theoretical prediction for hadronic cross sections, and in some cases even an all-order resummation of large perturbative corrections is …
Date: October 6, 2008
Creator: Vogelsang, W.
Object Type: Article
System: The UNT Digital Library
RHIC Polarized proton performance in run-8 (open access)

RHIC Polarized proton performance in run-8

During Run-8, the Relativistic Heavy Ion Collider (RHIC) provided collisions of spin-polarized proton beams at two interaction regions. Physics data were taken with vertical orientation of the beam polarization, which in the 'Yellow' RHIC ring was significantly lower than in previous years. We present recent developments and improvements as well as the luminosity and polarization performance achieved during Run-8, and we discuss possible causes of the not as high as previously achieved polarization performance of the 'Yellow' ring.
Date: October 6, 2008
Creator: Montag, C.; Bai, M.; MacKay, W. W.; Roser, T.; Abreu, N.; Ahrens, L. et al.
Object Type: Article
System: The UNT Digital Library
The Future of High Energy Polarized Proton Beams (open access)

The Future of High Energy Polarized Proton Beams

None
Date: October 6, 2008
Creator: Roser, T.
Object Type: Article
System: The UNT Digital Library
Selection and Implementation of a Replacement Cutting Tool Selection Application (open access)

Selection and Implementation of a Replacement Cutting Tool Selection Application

A new commercial cutting tool software package replaced an internally created legacy system. This report describes the issues that surfaced during the migration and installation of the commercial package and the solutions employed. The primary issues discussed are restructuring the data between two drastically different database schemas and the creation of individual component graphics.
Date: October 6, 2008
Creator: Rice, Gordon
Object Type: Report
System: The UNT Digital Library
Spin resonance strength calculations (open access)

Spin resonance strength calculations

In calculating the strengths of depolarizing resonances it may be convenient to reformulate the equations of spin motion in a coordinate system based on the actual trajectory of the particle, as introduced by Kondratenko, rather than the conventional one based on a reference orbit. It is shown that resonance strengths calculated by the conventional and the revised formalisms are identical. Resonances induced by radiofrequency dipoles or solenoids are also treated; with rf dipoles it is essential to consider not only the direct effect of the dipole but also the contribution from oscillations induced by it.
Date: October 6, 2008
Creator: Courant, E. D.
Object Type: Article
System: The UNT Digital Library
Predicting Efficient Antenna Ligands for Tb(III) Emission (open access)

Predicting Efficient Antenna Ligands for Tb(III) Emission

A series of highly luminescent Tb(III) complexes of para-substituted 2-hydroxyisophthalamide ligands (5LI-IAM-X) has been prepared (X = H, CH{sub 3}, (C=O)NHCH{sub 3}, SO{sub 3}{sup -}, NO{sub 2}, OCH{sub 3}, F, Cl, Br) to probe the effect of substituting the isophthalamide ring on ligand and Tb(III) emission in order to establish a method for predicting the effects of chromophore modification on Tb(III) luminescence. The energies of the ligand singlet and triplet excited states are found to increase linearly with the {pi}-withdrawing ability of the substituent. The experimental results are supported by time-dependent density functional theory (TD-DFT) calculations performed on model systems, which predict ligand singlet and triplet energies within {approx}5% of the experimental values. The quantum yield ({Phi}) values of the Tb(III) complex increases with the triplet energy of the ligand, which is in part due to the decreased non-radiative deactivation caused by thermal repopulation of the triplet. Together, the experimental and theoretical results serve as a predictive tool that can be used to guide the synthesis of ligands used to sensitize lanthanide luminescence.
Date: October 6, 2008
Creator: Samuel, Amanda P.S.; Xu, Jide & Raymond, Kenneth
Object Type: Article
System: The UNT Digital Library
Photoproduction at RHIC and the LHC (open access)

Photoproduction at RHIC and the LHC

The strong electromagnetic fields carried by relativistic highly charged ions make heavy-ion colliders attractive places to study photonuclear interactions and two-photon interactions. At RHIC, three experiments have studied coherent photoproduction of {rho}{sup 0}, 4{pi}, J/{psi}, e{sup +}e{sup -} pairs, and e{sup +}e{sup -} pairs where the electron is bound to one of the incident nuclei. These results show that photoproduction studies are possible, and demonstrate some of the unique possibilities due to the symmetric final states and the ion targets. The LHC will reach photon-nucleon energies many times higher than at HERA; these collisions can be used to measure the gluon distributions in nuclei at very low Bjorken-x, where shadowing and gluon saturation may become important; LHC {gamma}{gamma} collisions may also be attractive places to search for some types of new physics. ATLAS, CMS and ALICE are all planning to study photoproduction. After introducing the principles of photoproduction at hadron colliders, I will review recent results from RHIC on meson and e{sup +}e{sup -} production, and then discuss prospects for studies at the LHC.
Date: October 6, 2008
Creator: Klein, Spencer
Object Type: Article
System: The UNT Digital Library
Tough, bio-inspired hybrid materials (open access)

Tough, bio-inspired hybrid materials

The notion of mimicking natural structures in the synthesis of new structural materials has generated enormous interest but has yielded few practical advances. Natural composites achieve strength and toughness through complex hierarchical designs extremely difficult to replicate synthetically. Here we emulate Nature's toughening mechanisms through the combination of two ordinary compounds, aluminum oxide and polymethylmethacrylate, into ice-templated structures whose toughness can be over 300 times (in energy terms) that of their constituents. The final product is a bulk hybrid ceramic material whose high yield strength and fracture toughness ({approx}200 MPa and {approx}30 MPa{radical}m) provide specific properties comparable to aluminum alloys. These model materials can be used to identify the key microstructural features that should guide the synthesis of bio-inspired ceramic-based composites with unique strength and toughness.
Date: October 6, 2008
Creator: Munch, Etienne; Launey, Maximimilan E.; Alsem, Daan H.; Saiz, Eduardo; Tomsia, Antoni P. & Ritchie, Robert O.
Object Type: Article
System: The UNT Digital Library
NATO Enlargement: Albania, Croatia, and Possible Future Candidates (open access)

NATO Enlargement: Albania, Croatia, and Possible Future Candidates

This report discusses the current status of NATO membership following the April 2-4, 2008 NATO summit in Bucharest, Romania. A principal issue was consideration of the candidacies for membership of Albania, Croatia, and Macedonia. The allies agreed to extend invitations to Albania and Croatia. Although the alliance determined that Macedonia met the qualifications for NATO membership, Greece blocked the invitation due to an enduring dispute over Macedonia's name.
Date: October 6, 2008
Creator: Morelli, Vincent; Ek, Carl; Belkin, Paul; Woehrel, Steven & Nichol, Jim
Object Type: Report
System: The UNT Digital Library
Pipeline Safety and Security: Federal Programs (open access)

Pipeline Safety and Security: Federal Programs

This report discusses congressional interest in securing the nation's pipelines. Nearly half a million miles of oil and natural gas transmission pipeline crisscross the United States. While an efficient and fundamentally safe means of transport, many pipelines carry hazardous materials with the potential to cause public injury and environmental damage.
Date: October 6, 2008
Creator: Parfomak, Paul W.
Object Type: Report
System: The UNT Digital Library
Brazil-U.S. Relations (open access)

Brazil-U.S. Relations

This report analyzes Brazil's political, economic, and social conditions, and how those conditions affect its role in the region and its relationship with the United States.
Date: October 6, 2008
Creator: Seelke, Clare Ribando & Durand, Alessandra
Object Type: Report
System: The UNT Digital Library
Supreme Court Appellate Jurisdiction Over Military Court Cases (open access)

Supreme Court Appellate Jurisdiction Over Military Court Cases

This report surveys military courts' jurisdiction, the structure of appellate review for military cases, interactions between military and civilian courts, the Stevenson case, and the bills introduced in the 110th Congress.
Date: October 6, 2008
Creator: Henning, Anna C.
Object Type: Report
System: The UNT Digital Library
Administering Green Programs in Congress: Issues and Options (open access)

Administering Green Programs in Congress: Issues and Options

This report discusses "green" programs and the higher profile they have gained in the 110th Congress. "Green" programs are those designed to create an environmentally friendly work environment and conserve energy. This report discusses initiatives and policy options that would improve the "greening" process on Capitol Hill.
Date: October 6, 2008
Creator: Straus, Jacob R.
Object Type: Report
System: The UNT Digital Library

Faculty Recital: 2008-10-06 - Tony Baker, alto and tenor trombones and Steven Harlos, piano

Access: Use of this item is restricted to the UNT Community
Recital performed at the UNT College of Music Concert Hall.
Date: October 6, 2008
Creator: Baker, Tony (Trombonist) & Harlos, Steven, 1953-
Object Type: Sound
System: The UNT Digital Library
Interim Continuing Resolutions (CRs): Potential Impacts on Agency Operations (open access)

Interim Continuing Resolutions (CRs): Potential Impacts on Agency Operations

None
Date: October 6, 2008
Creator: Brass, Clinton T.
Object Type: Report
System: The UNT Digital Library
Real Earnings, Health Insurance and Pension Coverage, and the Distribution of Earnings, 1979-2007 (open access)

Real Earnings, Health Insurance and Pension Coverage, and the Distribution of Earnings, 1979-2007

None
Date: October 6, 2008
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Energy and Water Development: FY2009 Appropriations (open access)

Energy and Water Development: FY2009 Appropriations

None
Date: October 6, 2008
Creator: Behrens, Carl E.; Andrews, Anthony; Bearden, David M.; Carter, Nicole T.; Holt, Mark; Lane, Nic et al.
Object Type: Report
System: The UNT Digital Library