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Measurement of single-target spin asymmetries in the electroproduction of negative pions in the semi-inclusive deep inelastic reaction n{up_arrow}(e,e'{pi}{sup -})X on a transversely polarized {sup 3}He target (open access)

Measurement of single-target spin asymmetries in the electroproduction of negative pions in the semi-inclusive deep inelastic reaction n{up_arrow}(e,e'{pi}{sup -})X on a transversely polarized {sup 3}He target

The experiment E06010 measured the target single spin asymmetry (SSA) in the semiinclusive deep inelastic (SIDIS) n{up_arrow}(e, e'{pi}{sup -})X reaction with a transversely polarized {sup 3}He target as an e#11;ective neutron target. This is the very #12;rst independent measurement of the neutron SSA, following the measurements at HERMES and COMPASS on the proton and the deuteron. The experiment acquired data in Hall A at Je#11;erson Laboratory with a continuous electron beam of energy 5.9 GeV, probing the valence quark region, with x = 0.13 {rt_arrow} 0.41, at Q{sup 2} = 1.31 {rt_arrow} 3.1 GeV{sup 2}. The two contributing mechanisms to the measured asymmetry, viz, the Collins effect and the Sivers effect can be realized through the variation of the asymmetry as a function of the Collins and Sivers angles. The neutron Collins and Sivers moments, associated with the azimuthal angular modulations, are extracted from the measured asymmetry for the very #12;first time and are presented in this thesis. The kinematics of this experiment is comparable to the HERMES proton measurement. However, the COMPASS measurements on deuteron and proton are in the low-x region. The results of this experiment are crucial as the first step toward the extraction of quark transversity …
Date: June 1, 2010
Creator: Dutta, Chiranjib
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Subcellular localization of proteins in the anaerobic sulfate reducer Desulfovibrio vulgaris via SNAP-tag labeling and photoconversion (open access)

Subcellular localization of proteins in the anaerobic sulfate reducer Desulfovibrio vulgaris via SNAP-tag labeling and photoconversion

Systems Biology studies the temporal and spatial 3D distribution of macromolecular complexes with the aim that such knowledge will allow more accurate modeling of biological function and will allow mathematical prediction of cellular behavior. However, in order to accomplish accurate modeling precise knowledge of spatial 3D organization and distribution inside cells is necessary. And while a number of macromolecular complexes may be identified by its 3D structure and molecular characteristics alone, the overwhelming number of proteins will need to be localized using a reporter tag. GFP and its derivatives (XFPs) have been traditionally employed for subcelllar localization using photoconversion approaches, but this approach cannot be taken for obligate anaerobic bacteria, where the intolerance towards oxygen prevents XFP approaches. As part of the GTL-funded PCAP project (now ENIGMA) genetic tools have been developed for the anaerobe sulfate reducer Desulfovibrio vulgaris that allow the high-throughput generation of tagged-protein mutant strains, with a focus on the commercially available SNAP-tag cell system (New England Biolabs, Ipswich, MA), which is based on a modified O6-alkylguanine-DNA alkyltransferase (AGT) tag, that has a dead-end reaction with a modified O6-benzylguanine (BG) derivative and has been shown to function under anaerobic conditions. After initial challenges with respect to variability, …
Date: June 1, 2010
Creator: Gorur, A.; Leung, C. M.; Jorgens, D.; Tauscher, A.; Remis, J. P.; Ball, D. A. et al.
Object Type: Article
System: The UNT Digital Library
The Gut Microbiota: Ecology and Function (open access)

The Gut Microbiota: Ecology and Function

The gastrointestinal (GI) tract is teeming with an extremely abundant and diverse microbial community. The members of this community have coevolved along with their hosts over millennia. Until recently, the gut ecosystem was viewed as black box with little knowledge of who or what was there or their specific functions. Over the past decade, however, this ecosystem has become one of fastest growing research areas of focus in microbial ecology and human and animal physiology. This increased interest is largely in response to studies tying microbes in the gut to important diseases afflicting modern society, including obesity, allergies, inflammatory bowel diseases, and diabetes. Although the importance of a resident community of microorganisms in health was first hypothesized by Pasteur over a century ago (Sears, 2005), the multiplicity of physiological changes induced by commensal bacteria has only recently been recognized (Hooper et al., 2001). The term 'ecological development' was recently coined to support the idea that development of the GI tract is a product of the genetics of the host and the host's interactions with resident microbes (Hooper, 2004). The search for new therapeutic targets and disease biomarkers has escalated the need to understand the identities and functions of the microorganisms …
Date: June 1, 2010
Creator: Willing, B.P. & Jansson, J.K.
Object Type: Book
System: The UNT Digital Library
Review of “Deepwater Horizon Release Estimate of Rate by PIV” (open access)

Review of “Deepwater Horizon Release Estimate of Rate by PIV”

The Plume Calculation Team (PCT) conducted high quality work within a very short period of time, in spite of needing to use less than ideal quality videos provided by British Petroleum (BP), especially those made before the cutoff of the riser above the Blow Out Preventer (BOP) on June 3, 2010. There are at least two valid approaches for estimating the oil discharge coming out from the Deepwater Horizon broken pipeline and its riser, using BP videotapes. One method is to estimate the exit velocity directly with the use of the Particle Image Velocimetry (PIV). The second method is to use a buoyant plume analysis to determine the exit velocity. The PCT used both of these methods.
Date: June 1, 2010
Creator: Onishi, Yasuo
Object Type: Report
System: The UNT Digital Library
Nucleon matrix elements with Nf=2+1+1 maximally twisted fermions (open access)

Nucleon matrix elements with Nf=2+1+1 maximally twisted fermions

We present the first lattice calculation of nucleon matrix elements using four dynamical flavors. We use the Nf=2+1+1 maximally twisted mass formulation. The renormalization is performed non-perturbatively in the RI'-MOM scheme and results are given for the vector and axial vector operators with up to one-derivative. Our calculation of the average momentum of the unpolarized non-singlet parton distribution is presented and compared to our previous results obtained from the Nf=2 case.
Date: June 1, 2010
Creator: Simon Dinter, Constantia Alexandrou, Martha Constantinou, Vincent Drach, Karl Jansen, Dru Renner
Object Type: Article
System: The UNT Digital Library
Status of the TOUGH-FLAC simulator and recent applications related to coupled fluid flow and crustal deformations (open access)

Status of the TOUGH-FLAC simulator and recent applications related to coupled fluid flow and crustal deformations

This paper presents recent advancement in and applications of TOUGH-FLAC, a simulator for multiphase fluid flow and geomechanics. The TOUGH-FLAC simulator links the TOUGH family multiphase fluid and heat transport codes with the commercial FLAC{sup 3D} geomechanical simulator. The most significant new TOUGH-FLAC development in the past few years is a revised architecture, enabling a more rigorous and tight coupling procedure with improved computational efficiency. The applications presented in this paper are related to modeling of crustal deformations caused by deep underground fluid movements and pressure changes as a result of both industrial activities (the In Salah CO{sub 2} Storage Project and the Geysers Geothermal Field) and natural events (the 1960s Matsushiro Earthquake Swarm). Finally, the paper provides some perspectives on the future of TOUGH-FLAC in light of its applicability to practical problems and the need for high-performance computing capabilities for field-scale problems, such as industrial-scale CO{sub 2} storage and enhanced geothermal systems. It is concluded that despite some limitations to fully adapting a commercial code such as FLAC{sup 3D} for some specialized research and computational needs, TOUGH-FLAC is likely to remain a pragmatic simulation approach, with an increasing number of users in both academia and industry.
Date: June 1, 2010
Creator: Rutqvist, J.
Object Type: Article
System: The UNT Digital Library
Nucleon, Delta and Omega excited state spectra at three pion mass values (open access)

Nucleon, Delta and Omega excited state spectra at three pion mass values

The energies of the excited states of the Nucleon, Delta and Omega are computed in lattice QCD, using two light quarks and one strange quark on anisotropic lattices. The calculations are performed at three values of the pion mass: 392(4), 438(3) and 521(3) MeV. We employ the variational method with a basis of about ten interpolating operators enabling six energies to be distinguished clearly in each irreducible representation of the octahedral group. We compare our calculations of nucleon excited states with the low-lying experimental spectrum. There is reasonable agreement for the pattern of states.
Date: June 1, 2010
Creator: John Bulava, Robert G. Edwards, Balint Joo, David G. Richards, Eric Engelson, Huey-Wen Lin, Colin Morningstar, Stephen J. Wallace
Object Type: Article
System: The UNT Digital Library

Fermentation and Electrohydrogenic Approaches to Hydrogen Production

This work describes the development of a waste biomass fermentation process using cellulose-degrading bacteria for hydrogen production. This process is then integrated with an electrohydrogenesis process via the development of a microbial electrolysis cell reactor, during which fermentation waste effluent is further converted to hydrogen to increase the total output of hydrogen from biomass.
Date: June 1, 2010
Creator: Maness, P. C.; Thammannagowda, S.; Magnusson, L. & Logan, B.
Object Type: Presentation
System: The UNT Digital Library
[Email from Daniel Graney to a group email list about TSDC activities] (open access)

[Email from Daniel Graney to a group email list about TSDC activities]

Email from Daniel Graney to a group email list on June 1, 2010 discussing the final schedule for TSDC activities at State Democratic Convention.
Date: June 1, 2010
Creator: unknown
Object Type: Letter
System: The UNT Digital Library
Implementation of the Barcelona Basic Model into TOUGH-FLAC for simulations of the geomechanical behavior of unsaturated soils (open access)

Implementation of the Barcelona Basic Model into TOUGH-FLAC for simulations of the geomechanical behavior of unsaturated soils

This paper presents the implementation of the Barcelona Basic Model (BBM) into the TOUGH-FLAC simulator analyzing the geomechanical behavior of unsaturated soils. We implemented the BBM into TOUGH-FLAC by (1) extending an existing FLAC{sup 3D} module for the Modified Cam-Clay (MCC) model in FLAC{sup 3D} and (2) adding computational routines for suction-dependent strain and net stress (i.e., total stress minus gas pressure) for unsaturated soils. We implemented a thermo-elasto-plastic version of the BBM, wherein the soil strength depends on both suction and temperature. The implementation of the BBM into TOUGH-FLAC was verified and tested against several published numerical model simulations and laboratory experiments involving the coupled thermal-hydrological-mechanical (THM) behavior of unsaturated soils. The simulation tests included modeling the mechanical behavior of bentonite-sand mixtures, which are being considered as back-fill and buffer materials for geological disposal of spent nuclear fuel. We also tested and demonstrated the use of the BBM and TOUGH-FLAC for a problem involving the coupled THM processes within a bentonite-backfilled nuclear waste emplacement tunnel. The simulation results indicated complex geomechanical behavior of the bentonite backfill, including a nonuniform distribution of buffer porosity and density that could not be captured in an alternative, simplified, linear-elastic swelling model. As a …
Date: June 1, 2010
Creator: Rutqvist, J.; Ijiri, Y. & Yamamoto, H.
Object Type: Article
System: The UNT Digital Library
FY 2010 Third Quarter Report Comparison of Aerosol and Cloud Condensation Nuclei (CCN) Relationship Parameterizations with Data Collected During the 2008 VAMOS Ocean-Cloud-Atmosphere Land Study (VOCALS) Field Campaign (open access)

FY 2010 Third Quarter Report Comparison of Aerosol and Cloud Condensation Nuclei (CCN) Relationship Parameterizations with Data Collected During the 2008 VAMOS Ocean-Cloud-Atmosphere Land Study (VOCALS) Field Campaign

Metric for Quarter 3: Report comparisons of aerosol/CCN relationship parameterizations with data collected in the first quarter and best parameterization for VOCALS data set.
Date: June 1, 2010
Creator: Wang, J.; Daum, P. H.; Kleinman, L. L.; Lee, Y. N.; McGraw, R.; Sedlacek, A. J. et al.
Object Type: Text
System: The UNT Digital Library
Lessons Learned on Benchmarking from the International Human Reliability Analysis Empirical Study (open access)

Lessons Learned on Benchmarking from the International Human Reliability Analysis Empirical Study

The International Human Reliability Analysis (HRA) Empirical Study is a comparative benchmark of the prediction of HRA methods to the performance of nuclear power plant crews in a control room simulator. There are a number of unique aspects to the present study that distinguish it from previous HRA benchmarks, most notably the emphasis on a method-to-data comparison instead of a method-to-method comparison. This paper reviews seven lessons learned about HRA benchmarking from conducting the study: (1) the dual purposes of the study afforded by joining another HRA study; (2) the importance of comparing not only quantitative but also qualitative aspects of HRA; (3) consideration of both negative and positive drivers on crew performance; (4) a relatively large sample size of crews; (5) the use of multiple methods and scenarios to provide a well-rounded view of HRA performance; (6) the importance of clearly defined human failure events; and (7) the use of a common comparison language to “translate” the results of different HRA methods. These seven lessons learned highlight how the present study can serve as a useful template for future benchmarking studies.
Date: June 1, 2010
Creator: Boring, Ronald L.; Forester, John A.; Bye, Andreas; Dang, Vinh N. & Lois, Erasmia
Object Type: Article
System: The UNT Digital Library
CHARACTERIZATION OF RADIOACTIVITY IN THE REACTOR VESSEL OF THE HEAVY WATER COMPONENT TEST REACTOR (open access)

CHARACTERIZATION OF RADIOACTIVITY IN THE REACTOR VESSEL OF THE HEAVY WATER COMPONENT TEST REACTOR

The Heavy Water Component Test Reactor (HWCTR) facility is a pressurized heavy water reactor that was used to test candidate fuel designs for heavy water power reactors. The reactor operated at nominal power of 50 MW{sub th}. The reactor coolant loop operated at 1200 psig and 250 C. Two isolated test loop were designed into the reactor to provide special test conditions. Fig. 1 shows a cut-away view of the reactor. The two loops are contained in four inch diameter stainless steel piping. The HWCTR was operated for only a short duration, from March 1962 to December 1964 in order to test the viability of test fuel elements and other reactor components for use in a heavy water power reactor. The reactor achieved 13,882 MWd of total power while testing 36 different fuel assemblies. In the course of operation, HWCTR experienced the cladding failures of 10 separate test fuel assemblies. In each case, the cladding was breached with some release of fuel core material into the isolated test loop, causing fission product and actinide contamination in the main coolant loop and the liquid and boiling test loops. Despite the contribution of the contamination from the failed fuel, the primary source …
Date: June 1, 2010
Creator: Vinson, Dennis
Object Type: Article
System: The UNT Digital Library
Examination of the Regional Supply and Demand Balance for Renewable Electricity in the United States through 2015: Projecting from 2009 through 2015 (Revised) (open access)

Examination of the Regional Supply and Demand Balance for Renewable Electricity in the United States through 2015: Projecting from 2009 through 2015 (Revised)

This report examines the balance between the demand and supply of new renewable electricity in the United States on a regional basis through 2015. It expands on a 2007 NREL study that assessed the supply and demand balance on a national basis. As with the earlier study, this analysis relies on estimates of renewable energy supplies compared to demand for renewable energy generation needed to meet existing state renewable portfolio standard (RPS) policies in 28 states, as well as demand by consumers who voluntarily purchase renewable energy. However, it does not address demand by utilities that may procure cost-effective renewables through an integrated resource planning process or otherwise.
Date: June 1, 2010
Creator: Bird, L.; Hurlbut, D.; Donohoo, P.; Cory, K. & Kreycik, C.
Object Type: Report
System: The UNT Digital Library
Gas-Phase Molecular Dynamics: Theoretical Studies in Spectroscopy and Chemical Dynamics (open access)

Gas-Phase Molecular Dynamics: Theoretical Studies in Spectroscopy and Chemical Dynamics

The goal of this program is the development and application of computational methods for studying chemical reaction dynamics and molecular spectroscopy in the gas phase. We are interested in developing rigorous quantum dynamics algorithms for small polyatomic systems and in implementing approximate approaches for complex ones. Particular focus is on the dynamics and kinetics of chemical reactions and on the rovibrational spectra of species involved in combustion processes. This research also explores the potential energy surfaces of these systems of interest using state-of-the-art quantum chemistry methods.
Date: June 1, 2010
Creator: Yu, H. G. & Muckerman, J. T.
Object Type: Article
System: The UNT Digital Library
Greenhouse Gas Program Overview (Revised) (Fact Sheet) (open access)

Greenhouse Gas Program Overview (Revised) (Fact Sheet)

Overview of the Federal Energy Management Program (FEMP) Greenhouse Gas program, including Federal requirements, FEMP services, and contacts.
Date: June 1, 2010
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Enabling instrumentation and technology for 21st century light sources (open access)

Enabling instrumentation and technology for 21st century light sources

We present the summary from the Accelerator Instrumentation and Technology working group, one of the five working groups that participated in the BES-sponsored Workshop on Accelerator Physics of Future Light Sources held in Gaithersburg, MD September 15-17, 2009. We describe progress and potential in three areas: attosecond instrumentation, photon detectors for user experiments, and insertion devices.
Date: June 1, 2010
Creator: Byrd, J.M.; Shea, T.J.; Denes, P.; Siddons, P.; Attwood, D.; Kaertner, F. et al.
Object Type: Article
System: The UNT Digital Library
Better HMC integrators for dynamical simulations (open access)

Better HMC integrators for dynamical simulations

We show how to improve the molecular dynamics step of Hybrid Monte Carlo, both by tuning the integrator using Poisson brackets measurements and by the use of force gradient integrators. We present results for moderate lattice sizes.
Date: June 1, 2010
Creator: M.A. Clark, Balint Joo, A.D. Kennedy, P.J. Silva
Object Type: Article
System: The UNT Digital Library
Correlation Femtoscopy of Hyperons Produced in Interactions of Hyperons with Nuclei with 600 GeV Energy (open access)

Correlation Femtoscopy of Hyperons Produced in Interactions of Hyperons with Nuclei with 600 GeV Energy

None
Date: June 1, 2010
Creator: Romanov, Dmitry
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Charge Diagnostics for Laser Plasma Accelerators (open access)

Charge Diagnostics for Laser Plasma Accelerators

The electron energy dependence of a scintillating screen (Lanex Fast) was studied with sub-nanosecond electron beams ranging from 106 MeV to 1522 MeV at the Lawrence Berkeley National Laboratory Advanced Light Source (ALS) synchrotron booster accelerator. The sensitivity of the Lanex Fast decreased by 1percent per 100 MeV increase of the energy. The linear response of the screen against the charge was verified with charge density and intensity up to 160 pC/mm2 and 0.4 pC/ps/mm2, respectively. For electron beams from the laser plasma accelerator, a comprehensive study of charge diagnostics has been performed using a Lanex screen, an integrating current transformer, and an activation based measurement. The charge measured by each diagnostic was found to be within +/-10 percent.
Date: June 1, 2010
Creator: Nakamura, K.; Gonsalves, A. J.; Lin, C.; Sokollik, T.; Smith, A.; Rodgers, D. et al.
Object Type: Article
System: The UNT Digital Library
National Advanced Biofuels Consortium (NABC), Biofuels for Advancing America (Fact Sheet) (open access)

National Advanced Biofuels Consortium (NABC), Biofuels for Advancing America (Fact Sheet)

Introduction to the National Advanced Biofuels Consortium, a collaboration between 17 national laboratory, university, and industry partners that is conducting cutting-edge research to develop infrastructure-compatible, sustainable, biomass-based hydrocarbon fuels.
Date: June 1, 2010
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Photovoltaics (PV) as an Eligible Measure in Residential PACE Programs: Benefits and Challenges (Fact Sheet) (open access)

Photovoltaics (PV) as an Eligible Measure in Residential PACE Programs: Benefits and Challenges (Fact Sheet)

Property Assessed Clean Energy (PACE) financing is one of several new financial models broadening access to clean energy by addressing the barrier of initial capital cost. The majority of the PACE programs in the market today include PV as an eligible measure. PV appeals to homeowners as a way to reduce utility bills, self-generate sustainable power, increase energy independence and demonstrate a commitment to the environment. If substantial state incentives for PV exist, PV projects can be economic under PACE, especially when partnered with good net metering policies. At the same time, PV is expensive relative to other eligible measures with a return on investment horizon that might exceed program targets. This fact sheet reviews the benefits and potential challenges of including PV in PACE programs.
Date: June 1, 2010
Creator: Coughlin, J.
Object Type: Report
System: The UNT Digital Library
On a theory of neutrino oscillations with entanglement (open access)

On a theory of neutrino oscillations with entanglement

We show that the standard expression for the neutrino oscillation length can be confirmed even in theoretical approaches that take into account entanglement between the neutrino and its interaction partners. We show this in particular for the formalism developed in arXiv:1004.1847. Finally, we shed some light on the question why plane-wave approaches to the neutrino oscillation problem can yield the correct result for the oscillation length even though they do not explicitly account for the localization of the neutrino source and the detector.
Date: June 1, 2010
Creator: Kayser, Boris; Kopp, Joachim; Roberston, R. G. Hamish & Vogel, Petr
Object Type: Article
System: The UNT Digital Library
Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter (open access)

Update on the correlation of the highest energy cosmic rays with nearby extragalactic matter

Data collected by the Pierre Auger Observatory through 31 August 2007 showed evidence for anisotropy in the arrival directions of cosmic rays above the Greisen-Zatsepin-Kuzmin energy threshold, 6 x 10{sup 19} eV. The anisotropy was measured by the fraction of arrival directions that are less than 3.1{sup o} from the position of an active galactic nucleus within 75 Mpc (using the Veron-Cetty and Veron 12th catalog). An updated measurement of this fraction is reported here using the arrival directions of cosmic rays recorded above the same energy threshold through 31 December 2009. The number of arrival directions has increased from 27 to 69, allowing a more precise measurement. The correlating fraction is (38{sub -6}{sup +7})%, compared with 21% expected for isotropic cosmic rays. This is down from the early estimate of (69{sub -13}{sup +11})%. The enlarged set of arrival directions is examined also in relation to other populations of nearby extragalactic objects: galaxies in the 2 Microns All Sky Survey and active galactic nuclei detected in hard X-rays by the Swift Burst Alert Telescope. A celestial region around the position of the radiogalaxy Cen A has the largest excess of arrival directions relative to isotropic expectations. The 2-point autocorrelation function …
Date: June 1, 2010
Creator: Abreu, P.; /Lisbon, IST; Aglietta, M.; /Turin U. /INFN, Turin; Ahn, E.J.; /Fermilab et al.
Object Type: Article
System: The UNT Digital Library