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Loss of Rare Fish Species from Tropical Floodplain Food Webs Affects Community Structure and Ecosystem Multifunctionality in a Mesocosm Experiment (open access)

Loss of Rare Fish Species from Tropical Floodplain Food Webs Affects Community Structure and Ecosystem Multifunctionality in a Mesocosm Experiment

Article on the loss of rare fish species from tropical floodplain food webs and how this affects community structure and ecosystem multifunctionality in a mesocosm experiment.
Date: February 3, 2012
Creator: Pendleton, Richard M.; Hoeinghaus, David; Gomes, Luiz C. & Agostinho, Angela A.
System: The UNT Digital Library
Systematic Scale-Setting to All Orders: The Principle of Maximum Conformality and Commensurate Scale Relations (open access)

Systematic Scale-Setting to All Orders: The Principle of Maximum Conformality and Commensurate Scale Relations

None
Date: January 21, 2014
Creator: Brodsky, Stanley J.; Mojaza, Matin & Wu, Xing-Gang
System: The UNT Digital Library
Threefold Complementary Approach to Holographic QCD (open access)

Threefold Complementary Approach to Holographic QCD

None
Date: January 6, 2014
Creator: Brodsky, Stanley J.; de Teramond, Guy F. & Dosch, Hans Gunter
System: The UNT Digital Library
Studies of the 3D structure of the proton at Jlab (open access)

Studies of the 3D structure of the proton at Jlab

In recent years parton distributions, describing longitudinal momentum, helicity and transversity distributions of quarks and gluons, have been generalized to account also for transverse degrees of freedom. Two new sets of more general distributions, Transverse Momentum Distributions (TMDs) and Generalized Parton Distributions (GPDs) were introduced to describe transverse momentum and spatial distributions of partons. Great progress has been made since then in measurements of different Single Spin Asymmetries (SSAs) in semi-inclusive and hard exclusive processes, providing access to TMDs and GPDs, respectively. Studies of TMDs and GPDs are also among the main driving forces of the JLab 12 GeV upgrade project.
Date: January 1, 2014
Creator: Avakian, Harut A.
System: The UNT Digital Library
Evapotranspiration And Geochemical Controls On Groundwater Plumes At Arid Sites: Toward Innovative Alternate End-States For Uranium Processing And Tailings Facilities (open access)

Evapotranspiration And Geochemical Controls On Groundwater Plumes At Arid Sites: Toward Innovative Alternate End-States For Uranium Processing And Tailings Facilities

Management of legacy tailings/waste and groundwater contamination are ongoing at the former uranium milling site in Tuba City AZ. The tailings have been consolidated and effectively isolated using an engineered cover system. For the existing groundwater plume, a system of recovery wells extracts contaminated groundwater for treatment using an advanced distillation process. The ten years of pump and treat (P&T) operations have had minimal impact on the contaminant plume – primarily due to geochemical and hydrological limits. A flow net analysis demonstrates that groundwater contamination beneath the former processing site flows in the uppermost portion of the aquifer and exits the groundwater as the plume transits into and beneath a lower terrace in the landscape. The evaluation indicates that contaminated water will not reach Moenkopi Wash, a locally important stream. Instead, shallow groundwater in arid settings such as Tuba City is transferred into the vadose zone and atmosphere via evaporation, transpiration and diffuse seepage. The dissolved constituents are projected to precipitate and accumulate as minerals such as calcite and gypsum in the deep vadose zone (near the capillary fringe), around the roots of phreatophyte plants, and near seeps. The natural hydrologic and geochemical controls common in arid environments such as …
Date: January 8, 2014
Creator: Looney, Brian B.; Denham, Miles E.; Eddy-Dilek, Carol A.; Millings, Margaret R. & Kautsky, Mark
System: The UNT Digital Library
Prominent Methodist minister in Dallas to perform same-sex marriages in protest of church policy (open access)

Prominent Methodist minister in Dallas to perform same-sex marriages in protest of church policy

An online article about a new minister in the Dallas area that will perform marriage rights for LGBT couples.
Date: January 20, 2014
Creator: Wright, John
System: The UNT Digital Library
Engineering Metal Oxide Nanostructures for the Fiber Optic Sensor Platform (open access)

Engineering Metal Oxide Nanostructures for the Fiber Optic Sensor Platform

This article presents an effective integration scheme of nanostructured SnOâ‚‚ with the fiber optic platform for chemical sensing applications based on evanescent optical interactions.
Date: January 30, 2014
Creator: Poole, Zsolt; Ohodnicki, Paul; Chen, Rongzhang; Lin, Yuankun & Chen, Kevin P.
System: The UNT Digital Library
Nanopatterned Graphene Field Effect Transistor Fabricated Using Block Co-polymer Lithography (open access)

Nanopatterned Graphene Field Effect Transistor Fabricated Using Block Co-polymer Lithography

This article demonstrates a successful fabrication of Nanopatterened Graphene (NPG) using a PS-b-P4VP polymer.
Date: January 9, 2014
Creator: Choi, Duyoung; Kuru, Cihan; Choi, Chulmin; Noh, Kunbae; Hong, Soon-Kook; Das, Santanu et al.
System: The UNT Digital Library
Maximum of a function (open access)

Maximum of a function

In this article, the author presents a generalization of a certain Putnam problem.
Date: January 2014
Creator: Anghel, Nicolae
System: The UNT Digital Library
Implementing a Collaborative Workflow for Metadata Analysis, Quality Improvement, and Mapping (open access)

Implementing a Collaborative Workflow for Metadata Analysis, Quality Improvement, and Mapping

Article on implementing a collaborative workflow for metadata analysis, quality improvement, and mapping.
Date: January 17, 2014
Creator: Phillips, Mark Edward; Tarver, Hannah & Frakes, Stacy
System: The UNT Digital Library
Nonlinear Legendre Spectral Finite Elements for Wind Turbine Blade Dynamics: Preprint (open access)

Nonlinear Legendre Spectral Finite Elements for Wind Turbine Blade Dynamics: Preprint

This paper presents a numerical implementation and examination of new wind turbine blade finite element model based on Geometrically Exact Beam Theory (GEBT) and a high-order spectral finite element method. The displacement-based GEBT is presented, which includes the coupling effects that exist in composite structures and geometric nonlinearity. Legendre spectral finite elements (LSFEs) are high-order finite elements with nodes located at the Gauss-Legendre-Lobatto points. LSFEs can be an order of magnitude more efficient that low-order finite elements for a given accuracy level. Interpolation of the three-dimensional rotation, a major technical barrier in large-deformation simulation, is discussed in the context of LSFEs. It is shown, by numerical example, that the high-order LSFEs, where weak forms are evaluated with nodal quadrature, do not suffer from a drawback that exists in low-order finite elements where the tangent-stiffness matrix is calculated at the Gauss points. Finally, the new LSFE code is implemented in the new FAST Modularization Framework for dynamic simulation of highly flexible composite-material wind turbine blades. The framework allows for fully interactive simulations of turbine blades in operating conditions. Numerical examples showing validation and LSFE performance will be provided in the final paper.
Date: January 1, 2014
Creator: Wang, Q.; Sprague, M. A.; Jonkman, J. & Johnson, N.
System: The UNT Digital Library
Extraction of Transversity and Collins Functions (open access)

Extraction of Transversity and Collins Functions

We present a global re-analysis of recent experimental data on azimuthal asymmetries in semi-inclusive deep inelastic scattering, from the HERMES and COMPASS Collaborations, and in e{sup +}e{sup -} --> h_1h_2X processes, from the Belle Collaboration. The transversity distribution and the Collins functions are extracted simultaneously, in a revised analysis which also takes into account a new parameterization of the unknown functions.
Date: January 1, 2014
Creator: Anselmino, Mauro; Boglione, Mariaelena; D'Alesio, Umberto; Melis, Stefano; Murgia, Francesco & Prokudin, Alexei
System: The UNT Digital Library
Effects of Powder Morphology and Particle Size on CT Number Estimates (open access)

Effects of Powder Morphology and Particle Size on CT Number Estimates

None
Date: January 6, 2014
Creator: Kallman, J S; DePiero, S; Azevedo, S & Martz, H E
System: The UNT Digital Library
On the role of the Sivers effect in A{sub N} for inclusive particle production in pp collisions (open access)

On the role of the Sivers effect in A{sub N} for inclusive particle production in pp collisions

Single spin asymmetries, A{sub N} , for inclusive particle production in pp collisions are considered within a generalized parton model with inclusion of spin and tranverse momentum effects. We consider the potential role of the Sivers effect in A{sub N} , as extracted from a careful analysis of azimuthal asymmetries in SIDIS, and discuss its phenomenological consequences in connection with a recently updated study of the Collins effect.
Date: January 1, 2014
Creator: Anselmino, Mauro; Boglione, Mariaelena; D'Alesio, Umberto; Melis, Stefano; Murgia, Francesco & Prokudin, Alexei
System: The UNT Digital Library
Klystron Modulator System Incorporating a Pulsed Depressed Collector (open access)

Klystron Modulator System Incorporating a Pulsed Depressed Collector

None
Date: January 14, 2014
Creator: Kemp, Mark
System: The UNT Digital Library
Development of MMC Gamma Detectors for Nuclear Analysis (open access)

Development of MMC Gamma Detectors for Nuclear Analysis

None
Date: January 23, 2014
Creator: Bates, C. R.; Pies, C.; Kempf, S.; Gastaldo, L.; Fleischmann, A.; Enss, C. et al.
System: The UNT Digital Library
Upper Bound on the First Star Formation History (open access)

Upper Bound on the First Star Formation History

None
Date: January 9, 2014
Creator: Inoue, Yoshiyuki; Tanaka, Yasuyuki T.; Madejski, Grzegorz M. & Dominguez, Alberto
System: The UNT Digital Library
ILC Higgs White Paper (open access)

ILC Higgs White Paper

None
Date: January 9, 2014
Creator: Barklow, T.; Asner, D. M.; Calancha, C.; Fujii, K.; Graf, N.; Haber, H. E. et al.
System: The UNT Digital Library
Measurement of Excited Hyperons in Photoproduction at CLAS (open access)

Measurement of Excited Hyperons in Photoproduction at CLAS

Measurement results of photoproduced excited hyperon states using the CLAS detector at Jefferson Lab are shown. The invariant mass distribution of the {Lambda}(1405) has recently been shown to be different for each of the three Sigma pi channels that it decays to, showing that there is prominent interference between the isospin I=0 and I=1 isospin amplitudes. Measurements of the differential and total cross sections of the three hyperons {Lambda}(1405), {Sigma}{sup 0}(1385), and Lambda(1520) are presented and compared. Prospects of future studies using a 12 GeV beam with the GlueX detector are briefly given.
Date: January 1, 2014
Creator: Moriya, Kei & Schumacher, Reinhard A.
System: The UNT Digital Library
Sea quark transverse momentum distributions and dynamical chiral symmetry breaking (open access)

Sea quark transverse momentum distributions and dynamical chiral symmetry breaking

Recent theoretical studies have provided new insight into the intrinsic transverse momentum distributions of valence and sea quarks in the nucleon at a low scale. The valence quark transverse momentum distributions (q - qbar) are governed by the nucleon's inverse hadronic size R{sup -1} ~ 0.2 GeV and drop steeply at large p{sub T}. The sea quark distributions (qbar) are in large part generated by non-perturbative chiral-symmetry breaking interactions and extend up to the scale rho{sup -1} ~ 0.6 GeV. These findings have many implications for modeling the initial conditions of perturbative QCD evolution of TMD distributions (starting scale, shape of p{sub T}. distributions, coordinate-space correlation functions). The qualitative difference between valence and sea quark intrinsic p{sub T}. distributions could be observed experimentally, by comparing the transverse momentum distributions of selected hadrons in semi-inclusive deep-inelastic scattering, or those of dileptons produced in pp and pbar-p scattering.
Date: January 1, 2014
Creator: Schweitzer, Peter; Strikman, Mark & Weiss, Christian
System: The UNT Digital Library
Measurement Of Differential Cross Sections Of p(e,e'{pi}{sup +})n For High-Lying Resonances At Q{sup 2} < 5 GeV{sup 2} (open access)

Measurement Of Differential Cross Sections Of p(e,e'{pi}{sup +})n For High-Lying Resonances At Q{sup 2} < 5 GeV{sup 2}

The exclusive electro-production process $ep\to e^{\prime}n\pi^+$ was measured in the range of the invariant mass for $n\pi^+$ system $1.6~\rm{GeV}\le W \le 2.0~\rm{GeV}$, and the photon virtuality $1.8~\rm{GeV^2}\le Q^2\le4.0~\rm{GeV^2}$ using CLAS. For the first time, these kinematics are probed in exclusive $\pi^+$ production from the protons with nearly full coverage in the azimuthal and polar angles of the $n\pi^+$ center-of-mass system. In this experiment, approximately 39,000 differential cross-section data points were measured. In this proceeding, preliminary results of our latest analysis work are presented on differential cross sections and structure functions as well as Legendre Moments.
Date: January 1, 2014
Creator: Park, Kijun
System: The UNT Digital Library
Next-to-leading Order Diphoton 2-jet Production at the LHC (open access)

Next-to-leading Order Diphoton 2-jet Production at the LHC

None
Date: January 7, 2014
Creator: Bern, Z.; Dixon, L.J.; Cordero, F. Febres; Hoeche, S.; Ita, H.; Kosower, D. A. et al.
System: The UNT Digital Library
New Solutions with Accelerated Expansion in String Theory (open access)

New Solutions with Accelerated Expansion in String Theory

None
Date: January 13, 2014
Creator: Dodelson, Matthew; Dong, Xi; Silverstein, Eva & Torroba, Gonzalo
System: The UNT Digital Library
FAST Modular Wind Turbine CAE Tool: Nonmatching Spatial and Temporal Meshes: Preprint (open access)

FAST Modular Wind Turbine CAE Tool: Nonmatching Spatial and Temporal Meshes: Preprint

In this paper we propose and examine numerical algorithms for coupling time-dependent multi-physics modules relevant to computer-aided engineering (CAE) of wind turbines. In particular, we examine algorithms for coupling modules where spatial grids are non- matching at interfaces and module solutions are time advanced with different time increments and different time integrators. Sharing of data between modules is accomplished with a predictor-corrector approach, which allows for either implicit or explicit time integration within each module. Algorithms are presented in a general framework, but are applied to simple problems that are representative of the systems found in a whole-turbine analysis. Numerical experiments are used to explore the stability, accuracy, and efficiency of the proposed algorithms. This work is motivated by an in-progress major revision of FAST, the National Renewable Energy Laboratory's (NREL's) premier aero-elastic CAE simulation tool. The algorithms described here will greatly increase the flexibility and efficiency of FAST.
Date: January 1, 2014
Creator: Sprague, M. A.; Jonkman, J. M. & Jonkman, B. J.
System: The UNT Digital Library