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Geography, Archaeology, Art History: A Case Study for a Multidisciplinary Approach to Mapping Architectural Heritage (open access)

Geography, Archaeology, Art History: A Case Study for a Multidisciplinary Approach to Mapping Architectural Heritage

This article examines how technology may be incorporated into an art historical research program, through a cross-disciplinary project combining the visual methodologies of the art historian with the technical tack of the geographer.
Date: 2009
Creator: McCarty, Kim; Gregory, Britteny & Abel, Mickey S.
System: The UNT Digital Library
Who says I don’t want to come to school? School policies disenfranchise American Indian youth’s educational vision (open access)

Who says I don’t want to come to school? School policies disenfranchise American Indian youth’s educational vision

This article focuses on the importance of contextualizing school policies by illuminating how one school rule, In-School-Suspension (ISS) disengages students from the learning process.
Date: 2009
Creator: Quijada, Patricia D. & Murakami-Ramalho, Elizabeth
System: The UNT Digital Library
Evolution of Primary Hemostasis in Early Vertebrates (open access)

Evolution of Primary Hemostasis in Early Vertebrates

Article on the evolution of primary hemostasis in early vertebrates.
Date: December 23, 2009
Creator: Kim, Seongcheol; Carrillo, Maira; Kulkarni, Vrinda & Jagadeeswaran, Pudur
System: The UNT Digital Library
First-principles investigations of the dielectric properties of polypropylene/metal-oxide interfaces (open access)

First-principles investigations of the dielectric properties of polypropylene/metal-oxide interfaces

Article on first-principles investigations of the dielectric properties of polypropylene/metal-oxide interfaces. Nanoscale-resolved dielectric properties of polypropylene/metal-oxide (alumina, PbTiO₃) interfaces and of the corresponding surfaces are investigated via first-principles calculations.
Date: October 30, 2009
Creator: Yu, Liping; Ranjan, Vivek; Buongiorno Nardelli, Marco & Bernholc, Jerry
System: The UNT Digital Library
Metadata Quality Assurance: The University of North Texas Libraries' Experience (open access)

Metadata Quality Assurance: The University of North Texas Libraries' Experience

Article on metadata quality assurance and the experience of the University of North Texas (UNT) Libraries.
Date: 2009
Creator: Alemneh, Daniel Gelaw & Tarver, Hannah
System: The UNT Digital Library
It's not too Late for the Harpy Eagle (Harpia harpyja): High Levels of Genetic Diversity and Differentiation Can Fuel Conservation Programs (open access)

It's not too Late for the Harpy Eagle (Harpia harpyja): High Levels of Genetic Diversity and Differentiation Can Fuel Conservation Programs

Article on the harpy eagle (Harpia harpyja) and how high levels of genetic diversity and differentiation can fuel conservation programs.
Date: October 5, 2009
Creator: Lerner, Heather R. L.; Johnson, Jeff A.; Lindsay, Alec R.; Kiff, Lloyd F. & Mindell, David P.
System: The UNT Digital Library
The History Engine: Doing History with Digital Tools (open access)

The History Engine: Doing History with Digital Tools

Article on the History Engine Project, an online archive consisting of thousands of narratives written and contributed by undergraduates.
Date: September 9, 2009
Creator: Nelson, Robert K.; Nesbit, Scott & Torget, Andrew J., 1978-
System: The UNT Digital Library
MATE Transporters Facilitate Vacuolar Uptake of Epicatechin 3'-O-Glucoside for Proanthocyanidin Biosynthesis in Medicago truncatula and Arabidopsis (open access)

MATE Transporters Facilitate Vacuolar Uptake of Epicatechin 3'-O-Glucoside for Proanthocyanidin Biosynthesis in Medicago truncatula and Arabidopsis

Article discussing how MATE transporters facilitate vacuolar uptake of epicatechin 3'-O-glucoside for proanthocyanidin biosynthesis in Medicago truncatula and Arabidopsis.
Date: August 2009
Creator: Zhao, Jian & Dixon, R. A.
System: The UNT Digital Library
Heterodimeric geranyl(geranyl)diphosphate synthase from hop (Humulus lupulus) and the evolution of monoterpene biosynthesis (open access)

Heterodimeric geranyl(geranyl)diphosphate synthase from hop (Humulus lupulus) and the evolution of monoterpene biosynthesis

Article on heterodimeric geranyl(geranyl)diphosphate synthase from hop (Humulus lupulus) and the evolution of monoterpene biosynthesis.
Date: April 14, 2009
Creator: Wang, Guodong & Dixon, R. A.
System: The UNT Digital Library
Switchgrass (Panicum virgatum) possesses a divergent family of cinnamoyl CoA reductases with distinct biochemical properties (open access)

Switchgrass (Panicum virgatum) possesses a divergent family of cinnamoyl CoA reductases with distinct biochemical properties

Article on switchgrass (Panicum virgatum) possessing a divergent family of cinnamoyl CoA reductases with distinct biochemical properties.
Date: July 27, 2009
Creator: Escamilla-Treviño, Luis; Shen, Hui; Uppalapati, Srinivasa Rao; Ray, Tui; Tang, Yuhong; Hernandez, Timothy et al.
System: The UNT Digital Library
A WD40 Repeat Protein from Medicago truncatula Is Necessary for Tissue-Specific Anthocyanin and Proanthocyanidin Biosynthesis But Not for Trichome Development (open access)

A WD40 Repeat Protein from Medicago truncatula Is Necessary for Tissue-Specific Anthocyanin and Proanthocyanidin Biosynthesis But Not for Trichome Development

Article discussing how WD40 repeat protein from Medicago truncatula is necessary for tissue-specific anthocyanin and proanthocyanidin biosynthesis but not for trichome development.
Date: November 2009
Creator: Pang, Yongzhen; Wenger, Jonathan P.; Saathoff, Katie; Peel, Gregory J.; Wen, Jiangqi; Huhman, David et al.
System: The UNT Digital Library
Non-Markovian Nonstationary Completely Positive Open-Quantum-System Dynamics (open access)

Non-Markovian Nonstationary Completely Positive Open-Quantum-System Dynamics

This article discusses non-Markovian nonstationary completely positive open-quantum-system dynamics.
Date: August 4, 2009
Creator: Budini, Adrián A. & Grigolini, Paolo
System: The UNT Digital Library
Experimental Quenching of Harmonic Stimuli: Universality of Linear Response Theory (open access)

Experimental Quenching of Harmonic Stimuli: Universality of Linear Response Theory

This article discusses experimental quenching of harmonic stimuli.
Date: July 15, 2009
Creator: Allegrini, Paolo; Bologna, Mauro; Fronzoni, Leone; Grigolini, Paolo & Silvestri, Ludovico
System: The UNT Digital Library
Event-Driven Power-Law Relaxation in Weak Turbulence (open access)

Event-Driven Power-Law Relaxation in Weak Turbulence

This article discusses event-driven power-law relaxation in weak turbulence.
Date: January 5, 2009
Creator: Silvestri, Ludovico; Fronzoni, Leone; Grigolini, Paolo & Allegrini, Paolo
System: The UNT Digital Library
Complexity and Synchronization (open access)

Complexity and Synchronization

This article discusses complexity and synchronization in decision making and information transmission.
Date: August 14, 2009
Creator: Turalska, Malgorzata; Lukovic, Mirko; West, Bruce J. & Grigolini, Paolo
System: The UNT Digital Library
Recent charm mixing results from BABAR, Belle, and CDF (open access)

Recent charm mixing results from BABAR, Belle, and CDF

A summary of the results of several recent studies of charm mixing is presented. A number of different methods were used, including the measurement of lifetime ratios for final states of different CP, time dependence of wrong-sign hadronic decays, fits to time-dependent Dalitz plots, and searches for wrong-sign semi-leptonic decays. Taken together, they suggest mixing is of order 1%. The status of searches for indirect CP violation is also reported.
Date: February 2, 2009
Creator: Charles, M.J. & /SLAC, /Iowa U.
System: The UNT Digital Library
Time Reversal Violation (open access)

Time Reversal Violation

This talk briefly reviews three types of time-asymmetry in physics, which I classify as universal, macroscopic and microscopic. Most of the talk is focused on the latter, namely the violation of T-reversal invariance in particle physics theories. In sum tests of microscopic T-invariance, or observations of its violation, are limited by the fact that, while we can measure many processes, only in very few cases can we construct a matched pair of process and inverse process and observe it with sufficient sensitivity to make a test. In both the cases discussed here we can achieve an observable T violation making use of flavor tagging, and in the second case also using the quantum properties of an antisymmetric coherent state of two B mesons to construct a CP-tag. Both these tagging properties depend only on very general properties of the flavor and/or CP quantum numbers and so provide model independent tests for T-invariance violations. The microscopic laws of physics are very close to T-symmetric. There are small effects that give CP- and T-violating processes in three-generation-probing weak decays. Where a T-violating observable can be constructed we see the relationships between T-violation and CP-violation expected in a CPT conserving theory. These microscopic …
Date: January 27, 2009
Creator: Quinn, H.
System: The UNT Digital Library
Technical Risk Rating of DOE Environmental Projects - 9153 (open access)

Technical Risk Rating of DOE Environmental Projects - 9153

The U.S. Department of Energy's Office of Environmental Management (DOE-EM) was established to achieve the safe and compliant disposition of legacy wastes and facilities from defense nuclear applications. The scope of work is diverse, with projects ranging from single acquisitions to collections of projects and operations that span several decades and costs from hundreds of millions to billions US$. The need to be able to manage and understand the technical risks from the project to senior management level has been recognized as an enabler to successfully completing the mission. In 2008, DOE-EM developed the Technical Risk Rating as a new method to assist in managing technical risk based on specific criteria. The Technical Risk Rating, and the criteria used to determine the rating, provides a mechanism to foster open, meaningful communication between the Federal Project Directors and DOE-EM management concerning project technical risks. Four indicators (technical maturity, risk urgency, handling difficulty and resolution path) are used to focus attention on the issues and key aspects related to the risks. Pressing risk issues are brought to the forefront, keeping DOE-EM management informed and engaged such that they fully understand risk impact. Use of the Technical Risk Rating and criteria during reviews …
Date: February 11, 2009
Creator: Cercy, Michael; Fayfich, Ronald & Schneider, Steven
System: The UNT Digital Library
Measurement of the t anti-t production cross section and top quark mass extraction using dilepton events in p anti-p collisions (open access)

Measurement of the t anti-t production cross section and top quark mass extraction using dilepton events in p anti-p collisions

We present a measurement of the top quark pair production cross section in p{bar p} collisions at {radical}s = 1.96 TeV using approximately 1 fb{sup -1} of data collected with the D0 detector. We consider decay channels containing two high p{sub T} charged leptons where one lepton is identified as an electron or a muon while the other lepton can be an electron, a muon or a hadronically decaying {tau} lepton. For a mass of the top quark of 170 GeV, the measured cross section is 7.5{sub -1.0}{sup +1.0}(stat){sub -0.06}{sup +0.7}(syst){sub -0.5}{sup 0.6}(lumi) pb. Using {ell}{sub {tau}} events only, they measure: {sigma}{sub t{bar t}} x B(t{bar t} {yields} {ell}{sub {tau}}b{bar b}) = 0.13{sub -0.08}{sup +0.09}(stat){sub -0.06}{sup 0.06}(syst)+{sub -0.02}{sup +0.02}(lumi) pb. Comparing the measured cross section as a function of the mass of the top quark with a partial next-to-next-to leading order Quantum Chromodynamics theoretical prediction, we extract a mass of the top quark of 171.5{sub -8.8}{sup +9.9} GeV, in agreement with direct measurements.
Date: January 1, 2009
Creator: Abazov, V. M.; Abbott, B.; Abolins, M.; Acharya, B. S.; Adams, M.; Adams, T. et al.
System: The UNT Digital Library
High Resolution Simulation of Beam Dynamics in Electron Linacs for Free Electron Lasers (open access)

High Resolution Simulation of Beam Dynamics in Electron Linacs for Free Electron Lasers

In this paper we report on large scale multi-physics simulation of beam dynamics in electron linacs for next generation free electron lasers (FELs). We describe key features of a parallel macroparticle simulation code including three-dimensional (3D) space-charge effects, short-range structure wake fields, longitudinal coherent synchrotron radiation (CSR) wake fields, and treatment of radiofrequency (RF) accelerating cavities using maps obtained from axial field profiles. A macroparticle up-sampling scheme is described that reduces the shot noise from an initial distribution with a smaller number of macroparticles while maintaining the global properties of the original distribution. We present a study of the microbunching instability which is a critical issue for future FELs due to its impact on beam quality at the end of the linac. Using parameters of a planned FEL linac at Lawrence Berkeley National Laboratory (LBNL), we show that a large number of macroparticles (beyond 100 million) is needed to control numerical shot noise that drives the microbunching instability. We also explore the effect of the longitudinal grid on simulation results. We show that acceptable results are obtained with around 2048 longitudinal grid points, and we discuss this in view of the spectral growth rate predicted from linear theory. As an …
Date: January 5, 2009
Creator: Ryne, R.D.; Venturini, M.; Zholents, A.A. & Qiang, J.
System: The UNT Digital Library
CHANGING THE SAFETY CULTURE IN HANFORD TANK FARMS (open access)

CHANGING THE SAFETY CULTURE IN HANFORD TANK FARMS

In 2000 the Hanford Tank Farms had one of the worst safety records in the Department of Energy Complex. By the end of FY08 the safety performance of the workforce had turned completely around, resulting in one of the best safety records in the DOE complex for operations of its kind. This paper describes the variety of programs and changes that were put in place to accomplish such a dramatic turn-around. The U.S. Department of Energy's 586-square-mile Hanford Site in Washington State was established during World War II as part of the Manhattan Project to develop nuclear materials to end the war. For the next several decades it continued to produce plutonium for the nation's defense, leaving behind vast quantities of radioactive and chemical waste. Much of this waste, 53,000,000 gallons, remains stored in 149 aging single-shell tanks and 28 newer double-shell tanks. One of the primary objectives at Hanford is to safely manage this waste until it can be prepared for disposal, but this has not always been easy. These giant underground tanks, many of which date back to the beginning of the Manhattan Project, range in size from 55,000 gallons up to 1.1 million gallons, and are buried …
Date: January 6, 2009
Creator: MV, BERRIOCHOA & LJ, ALCALA
System: The UNT Digital Library
Measurement of the Semileptonic Decays B->D tau nu and B->D* tau nu (open access)

Measurement of the Semileptonic Decays B->D tau nu and B->D* tau nu

The authors present measurements of the semileptonic decays B{sup -} {yields} D{sup 0} {tau}{sup -} {bar {nu}}{sub {tau}}, B{sup -} {yields} D*{sup 0} {tau}{sup -}{bar {nu}}{sub {tau}}, {bar B}{sup 0} {yields} D{sup +} {tau}{sup -} {bar {nu}}{sub {tau}}, and {bar B}{sup 0} {yields} D*{sup +} {tau}{sup -}{bar {nu}}{sub {tau}}, which are sensitive to non-Standard Model amplitudes in certain scenarios. The data sample consists of 232 x 10{sup 6} {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} collider. They select events with a D or D* meson and a light lepton ({ell} = e or {mu}) recoiling against a fully reconstructed B meson. They perform a fit to the joint distribution of lepton momentum and missing mass squared to distinguish signal B {yields} D{sup (*)}{tau}{sup -} {bar {nu}}{sub {tau}} ({tau}{sup -} {yields} {ell}{sup -} {bar {nu}}{sub {ell}}{nu}{sub {tau}}) events from the backgrounds, predominantly B {yields} D{sup (*)} {ell}{sup -}{bar {nu}}{sub {ell}}. They measure the branching-fraction ratios R(D) {triple_bond} {Beta}(B {yields} D{tau}{sup -} {bar {nu}}{sub {tau}})/{Beta}(B {yields} D{ell}{sup -} {bar {nu}}{sub {ell}}) and R(D*) {triple_bond} {Beta}(B {yields} D*{tau}{sup -} {bar {nu}}{sub {tau}})/{Beta}(B {yields} D* {ell}{sup -} {bar {nu}}{sub {ell}}) and, from a combined fit …
Date: February 23, 2009
Creator: Aubert, B.
System: The UNT Digital Library
Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy (open access)

Limits on the Superconducting Order Parameter in NdFeAsO_{1-x}F_y from Scanning SQUID Microscopy

Identifying the symmetry of the superconducting order parameter in the recently-discovered ferrooxypnictide family of superconductors, RFeAsO{sub 1-x}F{sub y}, where R is a rare earth, is a high priority. Many of the proposed order parameters have internal {pi} phase shifts, like the d-wave order found in the cuprates, which would result in direction-dependent phase shifts in tunneling. In dense polycrystalline samples, these phase shifts in turn would result in spontaneous orbital currents and magnetization in the superconducting state. We perform scanning SQUID microscopy on a dense polycrystalline sample of NdFeAsO{sub 0.94}F{sub 0.06} with T{sub c} = 48K and find no such spontaneous currents, ruling out many of the proposed order parameters.
Date: January 8, 2009
Creator: Hicks, Clifford W.; Lippman, Thomas M.; Huber, Martin E.; Ren, Zhi-An; Yang, Jie; Zhao, Zhong-Xian et al.
System: The UNT Digital Library
Light-Front Holography and QCD Hadronization at the Amplitude Level (open access)

Light-Front Holography and QCD Hadronization at the Amplitude Level

Light-front holography allows hadronic amplitudes in the AdS/QCD fifth dimension to be mapped to frame-independent light-front wavefunctions of hadrons in physical space-time, thus providing a relativistic description of hadrons at the amplitude level. The AdS coordinate z is identified with an invariant light-front coordinate {zeta} which separates the dynamics of quark and gluon binding from the kinematics of constituent spin and internal orbital angular momentum. The result is a single-variable light-front Schroedinger equation for QCD which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular momentum. A new method for computing the hadronization of quark and gluon jets at the amplitude level using AdS/QCD light-front wavefunctions is outlined.
Date: January 9, 2009
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
System: The UNT Digital Library