AdS/QCD, LIight-Front Holography, and the Non-perturbative Running Coupling (open access)

AdS/QCD, LIight-Front Holography, and the Non-perturbative Running Coupling

The combination of Anti-de Sitter space (AdS) methods with light-front (LF) holography provides a remarkably accurate first approximation for the spectra and wavefunctions of meson and baryon light-quark bound states. The resulting bound-state Hamiltonian equation of motion in QCD leads to relativistic light-front wave equations in terms of an invariant impact variable {zeta} which measures the separation of the quark and gluonic constituents within the hadron at equal light-front time. These equations of motion in physical space-time are equivalent to the equations of motion which describe the propagation of spin-J modes in anti-de Sitter (AdS) space. The eigenvalues give the hadronic spectrum, and the eigenmodes represent the probability distributions of the hadronic constituents at a given scale. A positive-sign confining dilaton background modifying AdS space gives a very good account of meson and baryon spectroscopy and form factors. The light-front holographic mapping of this model also leads to a non-perturbative effective coupling {alpha}{sub s}{sup Ads} (Q{sup 2}) which agrees with the effective charge defined by the Bjorken sum rule and lattice simulations. It displays a transition from perturbative to nonperturbative conformal regimes at a momentum scale {approx} 1 GeV. The resulting {beta}-function appears to capture the essential characteristics of the …
Date: April 29, 2010
Creator: Brodsky, Stanley J.; de Teramond, Guy & Deur, Alexandre
System: The UNT Digital Library
The Arabidopsis lyrata genome sequence and the basis of rapid genome size change (open access)

The Arabidopsis lyrata genome sequence and the basis of rapid genome size change

In our manuscript, we present a high-quality genome sequence of the Arabidopsis thaliana relative, Arabidopsis lyrata, produced by dideoxy sequencing. We have performed the usual types of genome analysis (gene annotation, dN/dS studies etc. etc.), but this is relegated to the Supporting Information. Instead, we focus on what was a major motivation for sequencing this genome, namely to understand how A. thaliana lost half its genome in a few million years and lived to tell the tale. The rather surprising conclusion is that there is not a single genomic feature that accounts for the reduced genome, but that every aspect centromeres, intergenic regions, transposable elements, gene family number is affected through hundreds of thousands of cuts. This strongly suggests that overall genome size in itself is what has been under selection, a suggestion that is strongly supported by our demonstration (using population genetics data from A. thaliana) that new deletions seem to be driven to fixation.
Date: April 29, 2011
Creator: Hu, Tina T.; Pattyn, Pedro; Bakker, Erica G.; Cao, Jun; Cheng, Jan-Fang; Clark, Richard M. et al.
System: The UNT Digital Library
Atomic Physics Measurements in Support of X-Ray Astronomy (open access)

Atomic Physics Measurements in Support of X-Ray Astronomy

None
Date: April 29, 2011
Creator: Beiersdorfer, P
System: The UNT Digital Library
Corrigenda: Finite deformation of a pressurized magnetoelastic membrane in a stationary dipole field (open access)

Corrigenda: Finite deformation of a pressurized magnetoelastic membrane in a stationary dipole field

None
Date: April 29, 2011
Creator: Barham, M.; Steigmann, D. J.; McElfresh, M. & Rudd, R. E.
System: The UNT Digital Library
Enabling Fair Pricing on HPC Systems with Node Sharing (open access)

Enabling Fair Pricing on HPC Systems with Node Sharing

None
Date: April 29, 2013
Creator: Breslow, Alex D.; Tiwari, Ananta; Schulz, Martin; Carrington, Laura; Tang, Lingjia & Mars, Jason
System: The UNT Digital Library
Evidence for weak electronic correlations in Fe-pnictides (open access)

Evidence for weak electronic correlations in Fe-pnictides

Using x-ray absorption and resonant inelastic x-ray scattering, charge dynamics at and near the Fe L edges is investigated in Fe pnictide materials, and contrasted to that measured in other Fe compounds. It is shown that the XAS and RIXS spectra for 122 and 1111 Fe pnictides are each qualitatively similar to Fe metal. Cluster diagonalization, multiplet, and density-functional calculations show that Coulomb correlations are much smaller than in the cuprates, highlighting the role of Fe metallicity and strong covalency in these materials. Best agreement with experiment is obtained using Hubbard parameters U {approx}< 2eV and J {approx} 0.8eV.
Date: April 29, 2010
Creator: Yang, W.L.
System: The UNT Digital Library
Fabric Defect Detection Using Activation Layer Embedded Convolutional Neural Network (open access)

Fabric Defect Detection Using Activation Layer Embedded Convolutional Neural Network

This article develops a deep-learning algorithm for an on-loom fabric defect inspection system by combining the techniques of image pre-processing, fabric motif determination, candidate defect map generation, and convolutional neural networks (CNNs).
Date: April 29, 2019
Creator: Ouyang, Wenbin; Xu, Bugao; Hou, Jue & Yuan, Xiaohui
System: The UNT Digital Library
Finite temperature spin-dynamics and phase transitions in spin-orbital models (open access)

Finite temperature spin-dynamics and phase transitions in spin-orbital models

We study finite temperature properties of a generic spin-orbital model relevant to transition metal compounds, having coupled quantum Heisenberg-spin and Ising-orbital degrees of freedom. The model system undergoes a phase transition, consistent with that of a 2D Ising model, to an orbitally ordered state at a temperature set by short-range magnetic order. At low temperatures the orbital degrees of freedom freeze-out and the model maps onto a quantum Heisenberg model. The onset of orbital excitations causes a rapid scrambling of the spin spectral weight away from coherent spin-waves, which leads to a sharp increase in uniform magnetic susceptibility just below the phase transition, reminiscent of the observed behavior in the Fe-pnictide materials.
Date: April 29, 2010
Creator: Chen, C. C.
System: The UNT Digital Library
FOUR PI CALIBRATION AND MODELING OF A BARE GERMANIUM DETECTOR IN A CYLINDRICAL FIELD SOURCE (open access)

FOUR PI CALIBRATION AND MODELING OF A BARE GERMANIUM DETECTOR IN A CYLINDRICAL FIELD SOURCE

In reference 1 the authors described {gamma}-ray holdup assay of a Mossbauer spectroscopy instrument where they utilized two axial symmetric cylindrical shell acquisitions and two disk source acquisitions to determine Am-241 and Np-237 contamination. The measured contents of the two species were determined using a general detector efficiency calibration taken from a 12-inch point source.2 The authors corrected the raw spectra for container absorption as well as for geometry corrections to transform the calibration curve to the applicable axial symmetric cylindrical source - and disk source - of contamination. The authors derived the geometry corrections with exact calculus that are shown in equations (1) and (2) of our Experimental section. A cylindrical shell (oven source) acquisition configuration is described in reference 3, where the authors disclosed this configuration to gain improved sensitivity for holdup measure of U-235 in a ten-chamber oven. The oven was a piece of process equipment used in the Savannah River Plant M-Area Uranium Fuel Fabrication plant for which a U-235 holdup measurement was necessary for its decontamination and decommissioning in 2003.4 In reference 4 the authors calibrated a bare NaI detector for these U-235 holdup measurements. In references 5 and 6 the authors calibrated a bare …
Date: April 29, 2011
Creator: Dewberry, R. & Young, J.
System: The UNT Digital Library
Fueling the Future with Fungal Genomics (open access)

Fueling the Future with Fungal Genomics

Fungi play important roles across the range of current and future biofuel production processes. From crop/feedstock health to plant biomass saccharification, enzyme production to bioprocesses for producing ethanol, higher alcohols or future hydrocarbon biofuels, fungi are involved. Research and development are underway to understand the underlying biological processes and improve them to make bioenergy production efficient on an industrial scale. Genomics is the foundation of the systems biology approach that is being used to accelerate the research and development efforts across the spectrum of topic areas that impact biofuels production. In this review, we discuss past, current and future advances made possible by genomic analyses of the fungi that impact plant/feedstock health, degradation of lignocellulosic biomass and fermentation of sugars to ethanol, hydrocarbon biofuels and renewable chemicals.
Date: April 29, 2011
Creator: Grigoriev, Igor V.; Cullen, Daniel; Hibbett, David; Goodwin, Stephen B.; Jeffries, Thomas W.; Kubicek, Christian P. et al.
System: The UNT Digital Library
Gamma Spectrum from Neutron Capture on Tungsten Isotopes (open access)

Gamma Spectrum from Neutron Capture on Tungsten Isotopes

An evaluation of thermal neutron capture on the stable tungsten isotopes is presented, with preliminary results for the compound systems 183;184;185;187W. The evaluation procedure compares the g-ray cross-section data collected at the Budapest reactor, with Monte Carlo simulations of g-ray emission following the thermal neutron-capture process. The statistical-decay code DICEBOX was used for the Monte Carlo simulations. The evaluation yields new gamma rays in 185W and the confirmation of spins in 187W, raising the number of levels below which the level schemes are considered complete, thus increasing the number of levels that can be used in neutron data libraries.
Date: April 29, 2010
Creator: Hurst, Aaron; Summers, Neil; Sleaford, Brad; Firestone, Richard B; Belgya, T. & Revay, Z.S.
System: The UNT Digital Library
High power ring methods in ADS-R application (open access)

High power ring methods in ADS-R application

N/A
Date: April 29, 2013
Creator: F., Meot
System: The UNT Digital Library
Identifying tween fashion consumers’ profile concerning fashion innovativeness, opinion leadership, internet use for apparel shopping, interest in online co-design involvement, and brand commitment (open access)

Identifying tween fashion consumers’ profile concerning fashion innovativeness, opinion leadership, internet use for apparel shopping, interest in online co-design involvement, and brand commitment

Article describes study identifying tween fashion consumers’ profiles in relation to fashion change agent (FCA) characteristics, such as fashion innovativeness and opinion leadership, and examines how the tweens’ FCA characteristics influence their Internet innovativeness, interest in online co-design involvement, and brand commitment.
Date: April 29, 2019
Creator: Baker, Renee; Gam, Hae Jin & Banning, Jennifer
System: The UNT Digital Library
Integrated genomic and transcriptomic analysis reveals mycoparasitism as the ancestoral life style of Trichoderma (open access)

Integrated genomic and transcriptomic analysis reveals mycoparasitism as the ancestoral life style of Trichoderma

Mycoparasitism, a lifestyle where one fungus is parasitic on another fungus has special relevance when the prey is a plant pathogen, providing a strategy for biological control of pests for plant protection. Probably, the most studied biocontrol agents are species of the genus Hypocrea/Trichoderma.
Date: April 29, 2011
Creator: Kubicek, Christian P.; Herrera-Estrella, Alfredo; Seidl, Verena; Le Crom, Stéphane; Martinez, Diego A.; Druzhinina, Irina S. et al.
System: The UNT Digital Library
Introduction to Extra Dimensions (open access)

Introduction to Extra Dimensions

Extra dimensions provide a very useful tool in addressing a number of the fundamental problems faced by the Standard Model. The following provides a very basic introduction to this very broad subject area as given at the VIII School of the Gravitational and Mathematical Physics Division of the Mexican Physical Society in December 2009. Some prospects for extra dimensional searches at the 7 TeV LHC with {approx}1 fb{sup -1} of integrated luminosity are provided.
Date: April 29, 2010
Creator: Rizzo, Thomas G.
System: The UNT Digital Library
Limits on tau lepton flavor violating decays in three charged leptons (open access)

Limits on tau lepton flavor violating decays in three charged leptons

A search for the neutrinoless, lepton-flavor violating decay of the {tau} lepton into three charged leptons has been performed using an integrated luminosity of 468 fb{sup -1} collected with the BABAR detector at the PEP-II collider. In all six decay modes considered, the numbers of events found in data are compatible with the background expectations. Upper limits on the branching fractions are set in the range (1.8-3.3) x 10{sup -8} at 90% confidence level.
Date: April 29, 2010
Creator: Cervelli, Alberto
System: The UNT Digital Library
Lipoxygenase-mediated Oxidation of Polyunsaturated N-Acylethanolamines in Arabidopsis (open access)

Lipoxygenase-mediated Oxidation of Polyunsaturated N-Acylethanolamines in Arabidopsis

Article hypothesizing that lipoxygenase (LOX) participated in the metabolism of PU-NAEs through the formation of NAE-oxylipins. The data suggests that Arabidopsis LOXs indeed compete with FAAH to metabolize PU-NAEs during seedling establishment. Identification of endogenous amide-conjugated oxylipins suggests potential significance of these metabolites in vivo, and FAAH mutants may offer opportunities to address this in the future.
Date: April 29, 2011
Creator: Kilaru, Aruna; Herrfurth, Cornelia; Keereetaweep, Jantana; Hornung, Ellen; Venables, Barney J.; Feussner, Ivo et al.
System: The UNT Digital Library
Magnetoelasticity of highly deformable thin films: Theory and simulation (open access)

Magnetoelasticity of highly deformable thin films: Theory and simulation

None
Date: April 29, 2011
Creator: Barham, M I; Steigmann, D J & White, D
System: The UNT Digital Library
MALDI-MS Imaging of Urushiols in Poison Ivy Stem (open access)

MALDI-MS Imaging of Urushiols in Poison Ivy Stem

This article reports on the first analysis of urushiols in poison ivy stems by matrix-assisted laser desorption/ionization-mass spectrometry imaging (MALDI-MSI).
Date: April 29, 2017
Creator: Aziz, Mina; Sturtevant, Drew; Winston, Jordan; Collakova, Eva; Jelesko, John G. & Chapman, Kent D.
System: The UNT Digital Library
Measurement of Coherent Polarons in the Strongly Coupled Antiferromagnetically Ordered Iron-Chalcogenide Fe1:02Te using Angle-Resolved Photoemission Spectroscopy (open access)

Measurement of Coherent Polarons in the Strongly Coupled Antiferromagnetically Ordered Iron-Chalcogenide Fe1:02Te using Angle-Resolved Photoemission Spectroscopy

None
Date: April 29, 2013
Creator: Liu, Z. K.; He, R. H.; Lu, D. H.; Yi, M.; Chen, Y. L.; Hashimoto, M. et al.
System: The UNT Digital Library
A momentum-dependent perspective on quasiparticleinterference in Bi2Sr2CaCu2O_8+delta (open access)

A momentum-dependent perspective on quasiparticleinterference in Bi2Sr2CaCu2O_8+delta

Angle Resolved Photoemission Spectroscopy (ARPES) probes the momentum-space electronic structure of materials, and provides invaluable information about the high-temperature superconducting cuprates. Likewise, cuprates real-space, inhomogeneous electronic structure is elucidated by Scanning Tunneling Spectroscopy (STS). Recently, STS has exploited quasiparticle interference (QPI) - wave-like electrons scattering off impurities to produce periodic interference patterns - to infer properties of the QP in momentum-space. Surprisingly, some interference peaks in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+{delta}} (Bi-2212) are absent beyond the antiferromagnetic (AF) zone boundary, implying the dominance of particular scattering process. Here, we show that ARPES sees no evidence of quasiparticle (QP) extinction: QP-like peaks are measured everywhere on the Fermi surface, evolving smoothly across the AF zone boundary. This apparent contradiction stems from different natures of single-particle (ARPES) and two-particle (STS) processes underlying these probes. Using a simple model, we demonstrate extinction of QPI without implying the loss of QP beyond the AF zone boundary.
Date: April 29, 2010
Creator: Vishik, I. M.
System: The UNT Digital Library
Nanoindentation behavior of high entropy alloys with transformation-induced plasticity (open access)

Nanoindentation behavior of high entropy alloys with transformation-induced plasticity

Article describes an experiment where nanoindentation of three metastable dual-phase high entropy alloys (HEAs) was performed to obtain their inherent elastoplastic deformation responses.
Date: April 29, 2019
Creator: Sinha, S.; Mirshams, Reza; Wang, Tianhao; Nene, S. S.; Frank, M.; Liu, K et al.
System: The UNT Digital Library
On the Performance of an Algebraic MultigridSolver on Multicore Clusters (open access)

On the Performance of an Algebraic MultigridSolver on Multicore Clusters

Algebraic multigrid (AMG) solvers have proven to be extremely efficient on distributed-memory architectures. However, when executed on modern multicore cluster architectures, we face new challenges that can significantly harm AMG's performance. We discuss our experiences on such an architecture and present a set of techniques that help users to overcome the associated problems, including thread and process pinning and correct memory associations. We have implemented most of the techniques in a MultiCore SUPport library (MCSup), which helps to map OpenMP applications to multicore machines. We present results using both an MPI-only and a hybrid MPI/OpenMP model.
Date: April 29, 2010
Creator: Baker, A H; Schulz, M & Yang, U M
System: The UNT Digital Library
Origin of charge density at LaAlO3-on-SrTiO3 heterointerfacespossibility of intrinsic doping (open access)

Origin of charge density at LaAlO3-on-SrTiO3 heterointerfacespossibility of intrinsic doping

As discovered by Ohtomo et al., a large sheet charge density with high mobility exists at the interface between SrTiO{sub 3} and LaAlO{sub 3}. Based on transport, spectroscopic and oxygen-annealing experiments, we conclude that extrinsic defects in the form of oxygen vacancies introduced by the pulsed laser deposition process used by all researchers to date to make these samples is the source of the large carrier densities. Annealing experiments show a limiting carrier density. We also present a model that explains the high mobility based on carrier redistribution due to an increased dielectric constant.
Date: April 29, 2010
Creator: Siemons, W.
System: The UNT Digital Library