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Stress Variances Among Informal Hospice Caregivers (open access)

Stress Variances Among Informal Hospice Caregivers

Article on stress variances among informal hospice caregivers.
Date: August 2012
Creator: Wittenberg-Lyles, Elaine; Demiris, George; Oliver, Debra Parker; Washington, Karla T.; Burt, Stephanie & Shaunfield, Sara
System: The UNT Digital Library
On the Removal of Download Access to Grateful Dead Soundboards from the Live Music Archive (open access)

On the Removal of Download Access to Grateful Dead Soundboards from the Live Music Archive

Article on the removal of download access to Grateful Dead soundboards from the Live Music Archive.
Date: August 1, 2012
Creator: Berg, Jeremy
System: The UNT Digital Library
Extending the MC-SURE to Denoise Sensor Data Streams (open access)

Extending the MC-SURE to Denoise Sensor Data Streams

None
Date: August 3, 2012
Creator: Ndoye, M. & Kamath, C.
System: The UNT Digital Library
PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES (open access)

PRESERVATION OF H2 PRODUCTION ACTIVITY IN NANOPOROUS LATEX COATINGS OF RHODOPSEUDOMONAS PALUSTRIS CGA009 DURING DRY STORAGE AT AMBIENT TEMPERATURES

To assess the applicability of latex cell coatings as an "off-the-shelf' biocatalyst, the effect of osmoprotectants, temperature, humidity and O{sub 2} on preservation of H{sub 2} production in Rhodopseudomonas palustris coatings was evaluated. Immediately following latex coating coalescence (24 h) and for up to 2 weeks of dry storage, rehydrated coatings containing different osmoprotectants displayed similar rates of H{sub 2} production. Beyond 2 weeks of storage, sorbitol- treated coatings lost all H{sub 2} production activity, whereas considerable H{sub 2} production was still detected in sucrose- and trehalose-stabilized coatings. The relative humidity level at which the coatings were stored had a significant impact on the recovery and subsequent rates of H{sub 2} production. After 4 weeks storage under air at 60% humidity, coatings produced only trace amounts of H{sub 2} (0-0.1% headspace accumulation), whereas those stored at <5% humidity retained 27-53% of their H{sub 2} production activity after 8 weeks of storage. When stored in argon at <5% humidity and room temperature, R. palustris coatings retained full H{sub 2} production activity for 3 months, implicating oxidative damage as a key factor limiting coating storage. Overall, the results demonstrate that biocatalytic latex coatings are an attractive cell immobilization platform for preservation of …
Date: August 27, 2012
Creator: Milliken, C.; Piskorska, M.; Soule, T.; Gosse, J.; Flickinger, M.; Smith, G. et al.
System: The UNT Digital Library
High-temperature treatment of In-doped CZT crystals grown by the high-pressure Bridgman method (open access)

High-temperature treatment of In-doped CZT crystals grown by the high-pressure Bridgman method

We evaluated the effect of high-temperature treatment of Cd0.9Zn0.1Te:In single crystals using Hall-effect measurements, medium- and high-temperature annealing under various deviations from stoichiometry, and infra-red (IR) transmission microscopy Annealing at ~730 K sharply increased the electrical conductivity (by ~1-2 orders-of-magnitude). Plots of the temperature- and cadmium-pressure dependences of the electrical conductivity, carrier concentration, and mobility were obtained. Treating previously annealed Cd-samples under a Te overpressure at 1070 K allowed us to restore their resistance to its initial high values. The main difference in comparing this material with CdTe was its lowered electron density. We explained our results within the framework of Kröger’s theory of quasi-chemical reactions between point defects in solids.
Date: August 12, 2012
Creator: Bolotnikov, A.; Fochuk, P.; Nakonechnyi, I.; Kopach, O.; Verzhak, Ye.; Panchuk, O. et al.
System: The UNT Digital Library
Unresolved Puzzles in the X-ray Emission Produced by Charge Exchange Measured on Electron Beam Ion Traps (open access)

Unresolved Puzzles in the X-ray Emission Produced by Charge Exchange Measured on Electron Beam Ion Traps

None
Date: August 1, 2012
Creator: Beiersdorfer, P; Brown, G V; Clementson, J; Kilbourne, C A; Kelley, R L; Leutenegger, M A et al.
System: The UNT Digital Library
Counterintuitive MCNPX Results for Scintillator Surface Roughness Effect (open access)

Counterintuitive MCNPX Results for Scintillator Surface Roughness Effect

We have reported on our recent MCNPX simulation results of energy deposition for a group of 8 scintillation detectors, coupled with various rough surface patterns. The MCNPX results generally favored the detectors with various rough surface patterns. The observed MCNPX results are not fully explained by this work.
Date: August 12, 2012
Creator: unknown
System: The UNT Digital Library
Direct Observation of Hydrides Formation in Cavity-Grade Niobium (open access)

Direct Observation of Hydrides Formation in Cavity-Grade Niobium

None
Date: August 1, 2012
Creator: Barkov, F. & Romanenko, A.
System: The UNT Digital Library
A CASE STUDY OF CHLORINE TRANSPORT AND FATE FOLLOWING A LARGE ACCIDENTAL RELEASE (open access)

A CASE STUDY OF CHLORINE TRANSPORT AND FATE FOLLOWING A LARGE ACCIDENTAL RELEASE

A train derailment that occurred in Graniteville, South Carolina during the early morning hours of 06 January, 2005 resulted in the prompt release of approximately 60 tons of chlorine to the environment. Comprehensive modeling of the transport and fate of this release was performed including the characterization of the initial three-phased chlorine release, a detailed determination of the local atmospheric conditions acting to generate, disperse, and deplete the chlorine vapor cloud, the establishment of physical exchange mechanisms between the airborne vapor and local surface waters, and local aquatic dilution and mixing.
Date: August 1, 2012
Creator: Buckley, R.; Hunter, C.; Werth, D.; Whiteside, M.; Chen, K. & Mazzola, C.
System: The UNT Digital Library
Setting Whole-Building Absolute Energy Use Targets for the K-12 School, Retail, and Healthcare Sectors: Preprint (open access)

Setting Whole-Building Absolute Energy Use Targets for the K-12 School, Retail, and Healthcare Sectors: Preprint

This paper helps owners' efficiency representatives to inform executive management, contract development, and project management staff as to how specifying and applying whole-building absolute energy use targets for new construction or renovation projects can improve the operational energy performance of commercial buildings.
Date: August 1, 2012
Creator: Leach, M.; Bonnema, E.; Pless, S. & Torcellini, P.
System: The UNT Digital Library
Electronic Structure and Oxidation State Changes in the Mn (4) Ca Cluster of Photosystem II (open access)

Electronic Structure and Oxidation State Changes in the Mn (4) Ca Cluster of Photosystem II

Oxygen-evolving complex (Mn{sub 4}Ca cluster) of Photosystem II cycles through five intermediate states (S{sub i}-states, i = 0-4) before a molecule of dioxygen is released. During the S-state transitions, electrons are extracted from the OEC, either from Mn or alternatively from a Mn ligand. The oxidation state of Mn is widely accepted as Mn{sub 4}(III{sub 2},IV{sub 2}) and Mn{sub 4}(III,IV{sub 3}) for S{sub 1} and S{sub 2} states, while it is still controversial for the S{sub 0} and S{sub 3} states. We used resonant inelastic X-ray scattering (RIXS) to study the electronic structure of Mn{sub 4}Ca complex in the OEC. The RIXS data yield two-dimensional plots that provide a significant advantage by obtaining both K-edge pre-edge and L-edge-like spectra (metal spin state) simultaneously. We have collected data from PSII samples in the each of the S-states and compared them with data from various inorganic Mn complexes. The spectral changes in the Mn 1s2p{sub 3/2} RIXS spectra between the S-states were compared to those of the oxides of Mn and coordination complexes. The results indicate strong covalency for the electronic configuration in the OEC, and we conclude that the electron is transferred from a strongly delocalized orbital, compared to those in …
Date: August 17, 2012
Creator: Yano, J.; Pushkar, Y.; Messinger, J.; Bergmann, U.; Glatzel, P. & Yachandra, V. K.
System: The UNT Digital Library
Atomic data of tungsten for current and future uses in fusion and plasma science (open access)

Atomic data of tungsten for current and future uses in fusion and plasma science

None
Date: August 4, 2012
Creator: Clementson, J; Beiersdorfer, P & Lennartsson, T
System: The UNT Digital Library
2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012 (open access)

2012 ROCK DEFORMATION: FEEDBACK PROCESSES IN ROCK DEFORMATION GORDON RESEARCH CONFERENCE, AUGUST 19-24, 2012

Topics covered include: Failure At High Confining Pressure; Fluid-assisted Slip, Earthquakes & Fracture; Reaction-driven Cracking; Fluid Transport, Deformation And Reaction; Localized Fluid Transport And Deformation; Earthquake Mechanisms; Subduction Zone Dynamics And Crustal Growth.
Date: August 24, 2012
Creator: Kelemen, Peter
System: The UNT Digital Library
Examination of a Junction-Box Adhesion Test for Use in Photovoltaic Module Qualification: Preprint (open access)

Examination of a Junction-Box Adhesion Test for Use in Photovoltaic Module Qualification: Preprint

Engineering robust adhesion of the junction-box (j-box) is a hurdle typically encountered by photovoltaic (PV) module manufacturers during product development. There are historical incidences of adverse effects (e.g., fires) caused when the j-box/adhesive/module system has failed in the field. The addition of a weight to the j-box during the 'damp heat' IEC qualification test is proposed to verify the basic robustness of its adhesion system. The details of the proposed test will be described, in addition to the preliminary results obtained using representative materials and components. The described discovery experiments examine moisture-cured silicone, foam tape, and hot-melt adhesives used in conjunction with PET or glass module 'substrates.' To be able to interpret the results, a set of material-level characterizations was performed, including thermogravimetric analysis, differential scanning calorimetry, and dynamic mechanical analysis. PV j-boxes were adhered to a substrate, loaded with a prescribed weight, and then placed inside an environmental chamber (at 85C, 85% relative humidity). Some systems did not remain attached through the discovery experiments. Observed failure modes include delamination (at the j-box/adhesive or adhesive/substrate interface) and phase change/creep. The results are discussed in the context of the application requirements, in addition to the plan for the formal experiment supporting …
Date: August 1, 2012
Creator: Miller, D. C. & Wohlgemuth, J. H.
System: The UNT Digital Library
Agreement Between Local and Global Measurements of the London Penetration Depth (open access)

Agreement Between Local and Global Measurements of the London Penetration Depth

Recent measurements of the superconducting penetration depth in Ba(Fe{sub 1-x}Co{sub x}){sub 2}As{sub 2} appeared to disagree on the magnitude and curvature of {delta}{lambda}{sub ab}(T), even near optimal doping. These measurements were carried out on different samples grown by different groups. To understand the discrepancy, we use scanning SQUID susceptometry and a tunnel diode resonator to measure the penetration depth in a single sample. The penetration depth observed by the two techniques is identical with no adjustments. We conclude that any discrepancies arise from differences between samples, either in growth or crystal preparation.
Date: August 29, 2012
Creator: Lippman, Thomas M.; Kalisky, Beena; Kim, Hyunsoo; Tanatar, Makariy; Budko, Sergey L.; Canfield, Paul C. et al.
System: The UNT Digital Library
Fusion Driven Gamma and Fast Neutron Radiography Test-Bed at Lawrence Livermore National Laboratory (open access)

Fusion Driven Gamma and Fast Neutron Radiography Test-Bed at Lawrence Livermore National Laboratory

None
Date: August 1, 2012
Creator: Tang, V.; Falabella, S.; Rusnak, B.; Wang, H.; Hall, J. M.; McCarrick, J. F. et al.
System: The UNT Digital Library
Search for the Decay Modes D0 to e+ e-, D0 to mu+ mu-, and D0 to e+/- mu+/- (open access)

Search for the Decay Modes D0 to e+ e-, D0 to mu+ mu-, and D0 to e+/- mu+/-

We present searches for the rare decay modes D{sup 0} {yields} e{sup +}e{sup -}, D{sup 0} {yields} {mu}{sup +}{mu}{sup -}, and D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}} in continuum e{sup +}e{sup -} {yields} c{bar c} events recorded by the BABAR detector in a data sample that corresponds to an integrated luminosity of 468 fb{sup -1}. These decays are highly GIM suppressed but may be enhanced in several extensions of the Standard Model. Our observed event yields are consistent with the expected backgrounds. An excess is seen in the D{sup 0} {yields} {mu}{sup +}{mu}{sup -} channel, although the observed yield is consistent with an upward background fluctuation at the 5% level. Using the Feldman-Cousins method, we set the following 90% confidence level intervals on the branching fractions: {Beta}(D{sup 0} {yields} e{sup +}e{sup -}) < 1.7 x 10{sup -7}, {Beta}(D{sup 0} {yields} {mu}{sup +}{mu}{sup -}) within [0.6, 8.1] x 10{sup -7}, and {Beta}(D{sup 0} {yields} e{sup {+-}}{mu}{sup {-+}}) < 3.3 x 10{sup -7}.
Date: August 3, 2012
Creator: Lees, J. P.
System: The UNT Digital Library
Supporting Dynamic Spectrum Access in Heterogeneous LTE+ Networks (open access)

Supporting Dynamic Spectrum Access in Heterogeneous LTE+ Networks

As early as 2014, mobile network operators’ spectral capac- ity is expected to be overwhelmed by the demand brought on by new devices and applications. With Long Term Evo- lution Advanced (LTE+) networks likely as the future one world 4G standard, network operators may need to deploy a Dynamic Spectrum Access (DSA) overlay in Heterogeneous Networks (HetNets) to extend coverage, increase spectrum efficiency, and increase the capacity of these networks. In this paper, we propose three new management frameworks for DSA in an LTE+ HetNet: Spectrum Accountability Client, Cell Spectrum Management, and Domain Spectrum Man- agement. For these spectrum management frameworks, we define protocol interfaces and operational signaling scenar- ios to support cooperative sensing, spectrum lease manage- ment, and alarm scenarios for rule adjustment. We also quan- tify, through integer programs, the benefits of using DSA in an LTE+ HetNet, that can opportunistically reuse vacant TV and GSM spectrum. Using integer programs, we consider a topology using Geographic Information System data from the Blacksburg, VA metro area to assess the realistic benefits of DSA in an LTE+ HetNet.
Date: August 1, 2012
Creator: DaSilva, Luiz A.; Irwin, Ryan E. & Benonis, Mike
System: The UNT Digital Library
Positivity Preservation and Advection Algorithm Tests for Edge Plasma Turbulence (open access)

Positivity Preservation and Advection Algorithm Tests for Edge Plasma Turbulence

None
Date: August 8, 2012
Creator: Peterson, J L & Hammett, G W
System: The UNT Digital Library
Agent-based Cyber Control Strategy Design for Resilient Control Systems: Concepts, Architecture and Methodologies (open access)

Agent-based Cyber Control Strategy Design for Resilient Control Systems: Concepts, Architecture and Methodologies

The implementation of automated regulatory control has been around since the middle of the last century through analog means. It has allowed engineers to operate the plant more consistently by focusing on overall operations and settings instead of individual monitoring of local instruments (inside and outside of a control room). A similar approach is proposed for cyber security, where current border-protection designs have been inherited from information technology developments that lack consideration of the high-reliability, high consequence nature of industrial control systems. Instead of an independent development, however, an integrated approach is taken to develop a holistic understanding of performance. This performance takes shape inside a multiagent design, which provides a notional context to model highly decentralized and complex industrial process control systems, the nervous system of critical infrastructure. The resulting strategy will provide a framework for researching solutions to security and unrecognized interdependency concerns with industrial control systems.
Date: August 1, 2012
Creator: Rieger, Craig; Manic, Milos & McQueen, Miles
System: The UNT Digital Library
Surface Impedance Formalism for a Metallic Beam Pipe with Small Corrugations (open access)

Surface Impedance Formalism for a Metallic Beam Pipe with Small Corrugations

A metallic pipe with wall corrugations is of special interest in light of recent proposals to use such a pipe for the generation of terahertz radiation and for energy dechirping of electron bunches in free electron lasers. In this paper we calculate the surface impedance of a corrugated metal wall and show that it can be reduced to that of a thin layer with dielectric constant {epsilon} and magnetic permeability {mu}. We develop a technique for the calculation of these constants, given the geometrical parameters of the corrugations. We then calculate, for the specific case of a round metallic pipe with small corrugations, the frequency and strength of the resonant mode excited by a relativistic beam. Our analytical results are compared with numerical simulations, and are shown to agree well.
Date: August 30, 2012
Creator: Stupakov, G. & Bane, K. L. F.
System: The UNT Digital Library
Assembly and Packaging of a Wireless, Chronically-Implantable Neural Prosthetic Device (open access)

Assembly and Packaging of a Wireless, Chronically-Implantable Neural Prosthetic Device

None
Date: August 6, 2012
Creator: Shah, K G; DeLima, T; Benett, W; Felix, S; Sheth, H; Tolosa, V et al.
System: The UNT Digital Library
Progress on Development of the New FDIRC PID Detector (open access)

Progress on Development of the New FDIRC PID Detector

We present a progress status of a new concept of PID detector called FDIRC, intended to be used at the SuperB experiment, which requires {pi}/K separation up to a few GeV/c. The new photon camera is made of the solid fused-silica optics with a volume 25x smaller and speed increased by a factor of ten compared to the BaBar DIRC, and therefore will be much less sensitive to electromagnetic and neutron background
Date: August 3, 2012
Creator: Vavra, Jerry
System: The UNT Digital Library
Wind Power Forecasting Error Frequency Analyses for Operational Power System Studies: Preprint (open access)

Wind Power Forecasting Error Frequency Analyses for Operational Power System Studies: Preprint

The examination of wind power forecasting errors is crucial for optimal unit commitment and economic dispatch of power systems with significant wind power penetrations. This scheduling process includes both renewable and nonrenewable generators, and the incorporation of wind power forecasts will become increasingly important as wind fleets constitute a larger portion of generation portfolios. This research considers the Western Wind and Solar Integration Study database of wind power forecasts and numerical actualizations. This database comprises more than 30,000 locations spread over the western United States, with a total wind power capacity of 960 GW. Error analyses for individual sites and for specific balancing areas are performed using the database, quantifying the fit to theoretical distributions through goodness-of-fit metrics. Insights into wind-power forecasting error distributions are established for various levels of temporal and spatial resolution, contrasts made among the frequency distribution alternatives, and recommendations put forth for harnessing the results. Empirical data are used to produce more realistic site-level forecasts than previously employed, such that higher resolution operational studies are possible. This research feeds into a larger work of renewable integration through the links wind power forecasting has with various operational issues, such as stochastic unit commitment and flexible reserve level …
Date: August 1, 2012
Creator: Florita, A.; Hodge, B. M. & Milligan, M.
System: The UNT Digital Library