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Derivation of the evolution of empathic other-regarding social emotions as compared to non-social self-regarding emotions (open access)

Derivation of the evolution of empathic other-regarding social emotions as compared to non-social self-regarding emotions

Article accompanying a poster presentation for the 2012 Computational Neuroscience Annual Meeting. This article discusses the derivation of the evolution of empathic other-regarding social emotions as compared to non-social self-regarding emotions.
Date: July 16, 2012
Creator: Tam, Nicoladie D.
System: The UNT Digital Library
Complex Materials for Molecular Spintronics Applications: Cobalt Bis(dioxolene) Valence Tautomers, from Molecules to Polymers (open access)

Complex Materials for Molecular Spintronics Applications: Cobalt Bis(dioxolene) Valence Tautomers, from Molecules to Polymers

This article discusses complex materials for molecular spintronics applications.
Date: October 16, 2012
Creator: Calzolari, Arrigo; Chen, Yifeng; Lewis, Geoffrey F.; Dougherty, Daniel B.; Shultz, David A. & Buongiorno Nardelli, Marco
System: The UNT Digital Library
Cooperation-induced topological complexity: a promising road to fault tolerance and Hebbian learning (open access)

Cooperation-induced topological complexity: a promising road to fault tolerance and Hebbian learning

This article discusses cooperation-induced topological complexity and the emergence of intelligence.
Date: March 16, 2012
Creator: Turalska, Malgorzata; Geneston, Elvis L.; West, Bruce J.; Allegrini, Paolo & Grigolini, Paolo
System: The UNT Digital Library
Problem Solving Interventions: An Opportunity for Hospice Social Workers to Better Meet Caregiver Needs (open access)

Problem Solving Interventions: An Opportunity for Hospice Social Workers to Better Meet Caregiver Needs

Article on an opportunity for hospice social workers to better meet caregiver needs and problem solving interventions.
Date: March 16, 2012
Creator: Oliver, Debra Parker; Washington, Karla T.; Demiris, George; Wittenberg-Lyles, Elaine & Novak, Hannah
System: The UNT Digital Library
Using the X-FEL to understand X-ray Thomson scattering for partially ionized plasmas (open access)

Using the X-FEL to understand X-ray Thomson scattering for partially ionized plasmas

None
Date: July 16, 2012
Creator: Nilsen, J; Johnson, W R & Cheng, K T
System: The UNT Digital Library
A Non-Invasive Energy/Angle Diagnostic for Charged Particle Beams (open access)

A Non-Invasive Energy/Angle Diagnostic for Charged Particle Beams

A diagnostic for charged particle beams based on Compton scattering is presented. The particular case of an electron beam is treated in detail relativistically.
Date: March 16, 2012
Creator: Christensen, C. R.
System: The UNT Digital Library
2d Affine XY-Spin Model/4d Gauge Theory Duality and Deconfinement (open access)

2d Affine XY-Spin Model/4d Gauge Theory Duality and Deconfinement

We introduce a duality between two-dimensional XY-spin models with symmetry-breaking perturbations and certain four-dimensional SU(2) and SU(2) = Z{sub 2} gauge theories, compactified on a small spatial circle R{sup 1,2} x S{sup 1}, and considered at temperatures near the deconfinement transition. In a Euclidean set up, the theory is defined on R{sup 2} x T{sup 2}. Similarly, thermal gauge theories of higher rank are dual to new families of 'affine' XY-spin models with perturbations. For rank two, these are related to models used to describe the melting of a 2d crystal with a triangular lattice. The connection is made through a multi-component electric-magnetic Coulomb gas representation for both systems. Perturbations in the spin system map to topological defects in the gauge theory, such as monopole-instantons or magnetic bions, and the vortices in the spin system map to the electrically charged W-bosons in field theory (or vice versa, depending on the duality frame). The duality permits one to use the two-dimensional technology of spin systems to study the thermal deconfinement and discrete chiral transitions in four-dimensional SU(N{sub c}) gauge theories with n{sub f} {ge} 1 adjoint Weyl fermions.
Date: August 16, 2012
Creator: Anber, Mohamed M.; Poppitz, Erich; U., /Toronto; Unsal, Mithat & /SLAC /Stanford U., Phys. Dept. /San Francisco State U.
System: The UNT Digital Library
A Fisheye Lens as a Photonic Doppler Velocimetry Probe (open access)

A Fisheye Lens as a Photonic Doppler Velocimetry Probe

These presentation visuals report an instrument that, by use of a fish-eye lens, generates a beat signal using fiber mixing of unshifted light with Doppler-shifted light and measures the beat frequency. Ray trace diagrams are shown to illustrate advantages and disadvantages. The authors find their instrument has a long tracking distance, and large angle coverage. Index matching eases assembly, reduces return loss and flattens the field.
Date: August 16, 2012
Creator: Frogget, B. C.
System: The UNT Digital Library
Aerial Radiation Measurements from the Fukushima Dai-ichi Nuclear Power Plant Accident (open access)

Aerial Radiation Measurements from the Fukushima Dai-ichi Nuclear Power Plant Accident

This document is a slide show type presentation concerning DOE and Aerial Measuring System (AMS) activities and results with respect to assessing the consequences of the releases from the Fukushima Dai-ichi Nuclear Power Plant. These include ground monitoring and aerial monitoring.
Date: July 16, 2012
Creator: Guss, P. P.
System: The UNT Digital Library
Search for Dark Matter Satellites Using the FERMI-LAT (open access)

Search for Dark Matter Satellites Using the FERMI-LAT

Numerical simulations based on the {Lambda}CDM model of cosmology predict a large number of as yet unobserved Galactic dark matter satellites. We report the results of a Large Area Telescope (LAT) search for these satellites via the {gamma}-ray emission expected from the annihilation of weakly interacting massive particle (WIMP) dark matter. Some dark matter satellites are expected to have hard {gamma}-ray spectra, finite angular extents, and a lack of counterparts at other wavelengths. We sought to identify LAT sources with these characteristics, focusing on {gamma}-ray spectra consistent with WIMP annihilation through the b{bar b} channel. We found no viable dark matter satellite candidates using one year of data, and we present a framework for interpreting this result in the context of numerical simulations to constrain the velocity-averaged annihilation cross section for a conventional 100 GeV WIMP annihilating through the b{bar b} channel.
Date: August 16, 2012
Creator: Ackermann, M.; Albert, A.; Baldini, L.; Ballet, J.; Barbiellini, G.; Bastieri, D. et al.
System: The UNT Digital Library
Particle Energy Spectrum, Revisited from a Counting Statistics Perspective (open access)

Particle Energy Spectrum, Revisited from a Counting Statistics Perspective

This document is a slide show type presentation of a new covariance estimation for gamma spectra and neutron cross section.
Date: July 16, 2012
Creator: Yuan, D., Marks, D. G., Guss, P. P.
System: The UNT Digital Library
Coexistence of Two- and Three-dimensional Shubnikov-de Haas Oscillations in Ar^+ -irradiated KTaO_3 (open access)

Coexistence of Two- and Three-dimensional Shubnikov-de Haas Oscillations in Ar^+ -irradiated KTaO_3

We report the electron doping in the surface vicinity of KTaO{sub 3} by inducing oxygen-vacancies via Ar{sup +}-irradiation. The doped electrons have high mobility (> 10{sup 4} cm{sup 2}/Vs) at low temperatures, and exhibit Shubnikov-de Haas oscillations with both two- and three-dimensional components. A disparity of the extracted in-plane effective mass, compared to the bulk values, suggests mixing of the orbital characters. Our observations demonstrate that Ar{sup +}-irradiation serves as a flexible tool to study low dimensional quantum transport in 5d semiconducting oxides.
Date: May 16, 2012
Creator: Harashima, S.; Bell, C.; Kim, M.; Yajima, T.; Hikita, Y. & Hwang, H.Y.
System: The UNT Digital Library
Radiochronological Age of a Uranium Metal Sample from an Abandoned Facility (open access)

Radiochronological Age of a Uranium Metal Sample from an Abandoned Facility

A piece of scrap uranium metal bar buried in the dirt floor of an old, abandoned metal rolling mill was analyzed using multi-collector inductively coupled plasma mass spectroscopy (MC-ICP-MS). The mill rolled uranium rods in the 1940s and 1950s. Samples of the contaminated dirt in which the bar was buried were also analyzed. The isotopic composition of uranium in the bar and dirt samples were both the same as natural uranium, though a few samples of dirt also contained recycled uranium; likely a result of contamination with other material rolled at the mill. The time elapsed since the uranium metal bar was last purified can be determined by the in-growth of the isotope {sup 230}Th from the decay of {sup 234}U, assuming that only uranium isotopes were present in the bar after purification. The age of the metal bar was determined to be 61 years at the time of this analysis and corresponds to a purification date of July 1950 {+-} 1.5 years.
Date: March 16, 2012
Creator: Meyers, L. A.; Williams, R. W.; Glover, S. E.; LaMont, S. P.; Stalcup, A. M. & Spitz, H. B.
System: The UNT Digital Library
Final compression beamline systems for heavy ion fusion drivers (open access)

Final compression beamline systems for heavy ion fusion drivers

None
Date: July 16, 2012
Creator: Lau, Y. Y.; Yu, S. S.; Barnard, J. J. & Seidl, P. A.
System: The UNT Digital Library
Testing of CMOS Devices in NIF's Harsh Neutron Environment (open access)

Testing of CMOS Devices in NIF's Harsh Neutron Environment

None
Date: July 16, 2012
Creator: Teruya, A T; Bell, P M; Burns, S; Hagmann, C; Moody, J D & Richardson, M
System: The UNT Digital Library
Soft ionization of thermally evaporated hypergolic ionic liquid aerosols (open access)

Soft ionization of thermally evaporated hypergolic ionic liquid aerosols

Isolated ion pairs of a conventional ionic liquid, 1-Ethyl-3-Methyl-Imidazolium Bis(trifluoromethylsulfonyl)imide ([Emim+][Tf2N?]), and a reactive hypergolic ionic liquid, 1- Butyl-3-Methyl-Imidazolium Dicyanamide ([Bmim+][Dca?]), are generated by vaporizing ionic liquid submicron aerosol particles for the first time; the vaporized species are investigated by dissociative ionization with tunable vacuum ultraviolet (VUV) light, exhibiting clear intact cations, Emim+ and Bmim+, presumably originating from intact ion pairs. Mass spectra of ion pair vapor from an effusive source of the hypergolic ionic liquid show substantial reactive decomposition due to the internal energy of the molecules emanating from the source. Photoionization efficiency curves in the near threshold ionization region of isolated ion pairs of [Emim+][Tf2N?] ionic liquid vapor are compared for an aerosol source and an effusive source, revealing changes in the appearance energy due to the amount of internal energy in the ion pairs. The aerosol source has a shift to higher threshold energy (~;;0.3 eV), attributed to reduced internal energy of the isolated ion pairs. The method of ionic liquid submicron aerosol particle vaporization, for reactive ionic liquids such as hypergolic species, is a convenient, thermally ?cooler? source of isolated intact ion pairs in the gas phase compared to effusive sources.
Date: March 16, 2012
Creator: Koh, Christine J.; Liu, Chen-Lin; Harmon, Christopher W.; Strasser, Daniel; Golan, Amir; Kostko, Oleg et al.
System: The UNT Digital Library
A Radiating Shock Evaluated Using Implicit Monte Carlo Diffusion (open access)

A Radiating Shock Evaluated Using Implicit Monte Carlo Diffusion

None
Date: October 16, 2012
Creator: Cleveland, M. & Gentile, N.
System: The UNT Digital Library
Using Data Mining to Enable Integration of Wind Resources on the Power Grid (open access)

Using Data Mining to Enable Integration of Wind Resources on the Power Grid

None
Date: June 16, 2012
Creator: Kamath, C & Fan, Y J
System: The UNT Digital Library
Identification of L-Shell Transitions in M-shell Iron Ions in the Spectra of Capella and Procyon (open access)

Identification of L-Shell Transitions in M-shell Iron Ions in the Spectra of Capella and Procyon

None
Date: August 16, 2012
Creator: Lepson, J K; Beiersdorfer, P; Brown, G V; Trabert, E; Bode, M P; Desai, P et al.
System: The UNT Digital Library
Conditioning analysis of incomplete Cholesky factorizations with orthogonal dropping (open access)

Conditioning analysis of incomplete Cholesky factorizations with orthogonal dropping

The analysis of preconditioners based on incomplete Cholesky factorization in which the neglected (dropped) components are orthogonal to the approximations being kept is presented. General estimate for the condition number of the preconditioned system is given which only depends on the accuracy of individual approximations. The estimate is further improved if, for instance, only the newly computed rows of the factor are modified during each approximation step. In this latter case it is further shown to be sharp. The analysis is illustrated with some existing factorizations in the context of discretized elliptic partial differential equations.
Date: March 16, 2012
Creator: Napov, Artem
System: The UNT Digital Library
Design and testing of a megapixel CMOS charge dump and read camera (open access)

Design and testing of a megapixel CMOS charge dump and read camera

None
Date: July 16, 2012
Creator: Kimbrough, J. R.; Moody, J. D. & Bell, P. M.
System: The UNT Digital Library
Conference Report High Performance Computing for Policy Formulation - The Benefits and Risks - (open access)

Conference Report High Performance Computing for Policy Formulation - The Benefits and Risks -

None
Date: July 16, 2012
Creator: Rowley, D P
System: The UNT Digital Library
Precision Magnet Measurements for X-Band Accelerator Quadrupole Triplets (open access)

Precision Magnet Measurements for X-Band Accelerator Quadrupole Triplets

An X-band test station is being developed at LLNL to investigate accelerator optimization for future upgrades to mono-energetic gamma-ray (MEGa-Ray) technology at LLNL. Beamline magnets will include an emittance compensation solenoid, windowpane steering dipoles, and quadrupole magnets. Demanding tolerances have been placed on the alignment of these magnets, which directly affects the electron bunch beam quality. A magnet mapping system has been established at LLNL in order to ensure the delivered magnets match their field specification, and the mountings are aligned and capable of reaching the specified alignment tolerances. The magnet measurement system will be described which uses a 3-axis Lakeshore gauss probe mounted on a 3-axis translation stage. Alignment accuracy and precision will be discussed, as well as centering measurements and analysis. The dependence on data analysis over direct multi-pole measurement allows a significant improvement in useful alignment information. Detailed analysis of measurements on the beamline quadrupoles will be discussed, including multi-pole content both from alignment of the magnets, and the intrinsic level of multi-pole magnetic field.
Date: May 16, 2012
Creator: Marsh, R A; Anderson, S G & Armstrong, J P
System: The UNT Digital Library
AdS/QCD, Light-Front Holography, and Sublimated Gluons (open access)

AdS/QCD, Light-Front Holography, and Sublimated Gluons

The gauge/gravity duality leads to a simple analytical and phenomenologically compelling nonperturbative approximation to the full light-front QCD Hamiltonian - 'Light-Front Holography', which provides a Lorentz-invariant first-approximation to QCD, and successfully describes the spectroscopy of light-quark meson and baryons, their elastic and transition form factors, and other hadronic properties. The bound-state Schroedinger and Dirac equations of the soft-wall AdS/QCD model predict linear Regge trajectories which have the same slope in orbital angular momentum L and radial quantum number n for both mesons and baryons. Light-front holography connects the fifth-dimensional coordinate of AdS space z to an invariant impact separation variable {zeta} in 3+1 space at fixed light-front time. A key feature is the determination of the frame-independent light-front wavefunctions of hadrons - the relativistic analogs of the Schroedinger wavefunctions of atomic physics which allow one to compute form factors, transversity distributions, spin properties of the valence quarks, jet hadronization, and other hadronic observables. One thus obtains a one-parameter color-confining model for hadron physics at the amplitude level. AdS/QCD also predicts the form of the non-perturbative effective coupling {alpha}{sub s}{sup AdS} (Q) and its {beta}-function with an infrared fixed point which agrees with the effective coupling a{sub g1} (Q{sup 2}) extracted …
Date: February 16, 2012
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
System: The UNT Digital Library