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Using GIS technology to identify areas of tuberculosis transmission and incidence (open access)

Using GIS technology to identify areas of tuberculosis transmission and incidence

This article discusses using GIS technology to identify areas of tuberculosis transmission and incidence.
Date: October 13, 2004
Creator: Moonan, Patrick K.; Bayona, Manuel; Quitugua, Teresa N.; Oppong, Joseph R.; Dunbar, Denise; Jost, Kenneth C. et al.
System: The UNT Digital Library
Regiospecific hydroxylation of isoflavones by cytochrome P450 81E enzymes from Medicago truncatula (open access)

Regiospecific hydroxylation of isoflavones by cytochrome P450 81E enzymes from Medicago truncatula

Article on regiospecific hydroxylation of isoflavones by cytochrome P450 81E enzymes from Medicago truncatula.
Date: October 13, 2003
Creator: Liu, Chang-Jun; Huhman, David; Sumner, Lloyd W. & Dixon, R. A.
System: The UNT Digital Library
Mechanism and modeling of the formation of gaseous alkali sulfates (open access)

Mechanism and modeling of the formation of gaseous alkali sulfates

Article on the mechanism and modeling of the formation of gaseous alkali sulfates.
Date: October 13, 2004
Creator: Glarborg, Peter & Marshall, Paul
System: The UNT Digital Library
["The New Face of Gay Power" article, October 13, 2003] (open access)

["The New Face of Gay Power" article, October 13, 2003]

An article, written by John Cloud for Time Magazine, about Cody, Wyoming five years after the murder of a young gay man named Matthew Shepard. It is one of the more liberal cities in the state and is also home to one of the Republican Unity Coalition's chairmen, Alan Simpson.
Date: October 13, 2003
Creator: Cloud, John
System: The UNT Digital Library
Low-enriched uranium-molybdenum fuel plate development. (open access)

Low-enriched uranium-molybdenum fuel plate development.

None
Date: October 13, 2000
Creator: Wiencek, T. C. & Prokofiev, I. G.
System: The UNT Digital Library
Relativistic quantum dynamics of many-body systems. (open access)

Relativistic quantum dynamics of many-body systems.

None
Date: October 13, 2000
Creator: Coester, F. & Polyzou, W. N.
System: The UNT Digital Library
Disposal of Draeger Tubes at Savannah River Site (open access)

Disposal of Draeger Tubes at Savannah River Site

The Savannah River Site (SRS) is a Department of Energy (DOE) facility located in Aiken, South Carolina that is operated by the Westinghouse Savannah River Company (WSRC). At SRS Draeger tubes are used to identify the amount and type of a particular chemical constituent in the atmosphere. Draeger tubes rely on a chemical reaction to identify the nature and type of a particular chemical constituent in the atmosphere. Disposal practices for these tubes were identified by performing a hazardous waste evaluation per the Resource Conservation and Recovery Act (RCRA). Additional investigations were conducted to provide guidance for their safe handling, storage and disposal. A list of Draeger tubes commonly used at SRS was first evaluated to determine if they contained any material that could render them as a RCRA hazardous waste. Disposal techniques for Draeger tubes that contained any of the toxic contaminants listed in South Carolina Hazardous Waste Management Regulations (SCHWMR) R.61-79. 261.24 (b) and/or contained an acid in the liquid form were addressed.
Date: October 13, 2000
Creator: Malik, N.P.
System: The UNT Digital Library
Optimization of PET system design for lesion detection (open access)

Optimization of PET system design for lesion detection

Traditionally, the figures of merit used in designing a PET scanner are spatial resolution, noise equivalent count rate, noise equivalent sensitivity, etc. These measures, however, do not directly reflect the lesion detectability using the PET scanner. Here we propose to optimize PET scanner design directly for lesion detection. The signal-to-noise ratio (SNR) of lesion detection can be easily computed using the theoretical expressions that we have previously derived. Because no time consuming Monte Carlo simulation is needed, the theoretical expressions allow evaluation of a large range of parameters. The PET system parameters can then be chosen to achieve the maximum SNR for lesion detection. The simulation study shown in this paper was focused a single ring PET scanner without depth of interaction measurement. Randoms and scatters were also ignored.
Date: October 13, 2000
Creator: Qi, Jinyi
System: The UNT Digital Library
Synthesis of superlow friction carbon films from highly hydrogenated methane plasmas. (open access)

Synthesis of superlow friction carbon films from highly hydrogenated methane plasmas.

In this study, we investigated the friction and wear performance of diamondlike carbon films (DLC) derived from increasingly hydrogenated methane plasmas. The films were deposited on steel substrates by a plasma-enhanced chemical vapor deposition process at room temperature and the tribological tests were performed in dry nitrogen. Tests results revealed a close correlation between the hydrogen in source gas plasma and the friction and wear coefficients of the DLC films. Specifically, films grown in plasmas with higher hydrogen-to-carbon ratios had much lower friction coefficients and wear rates than did films derived from source gases with lower hydrogen-to-carbon ratios. The lowest friction coefficient (0.003) was achieved with a film derived from 25% methane--75% hydrogen, while a coefficient of 0.015 was found for films derived from pure methane. Similar correlations were observed for wear rates. Films derived from hydrogen-rich plasmas had the least wear, while films derived from pure methane suffered the highest wear. We used a combination of surface analytical methods to characterize the structure and chemistry of the DLC films and worn surfaces.
Date: October 13, 2000
Creator: Erdemir, A.; Eryilmaz, O. L.; Nilufer, I. B. & Fenske, G. R.
System: The UNT Digital Library
Long baseline neutrino oscillations: Parameter degeneracies and JHF/NuMI complementarity (open access)

Long baseline neutrino oscillations: Parameter degeneracies and JHF/NuMI complementarity

A summary of the parameter degeneracy issue for long baseline neutrino oscillations is presented and how a sequence of measurements can be used to resolve all degeneracies. Next, a comparison of the JHF and NuMI Off-Axis proposals is made with emphasis on how both experiments running neutrinos can distinguish between the normal and inverted hierarchies provided the E/L of NuMI is less than or equal to the E/L of JHF. Due to the space limitations of this proceedings only an executive style summary can be presented here, but the references and transparencies of the talk contain the detailed arguments.
Date: October 13, 2003
Creator: Parke, Stephen; Minakata, Hisakazu & Nunokawa, Hiroshi
System: The UNT Digital Library
Underlying event studies at CDF (open access)

Underlying event studies at CDF

We present recent studies about the ''underlying event'' which originates mostly from soft spectator interactions. First Run II data results are compared to published Run I results and to QCD Monte Carlo models.
Date: October 13, 2003
Creator: Lami, S.
System: The UNT Digital Library
Charm and beauty at the Tevatron (open access)

Charm and beauty at the Tevatron

The large heavy quark production cross section in p{bar p} collisions makes the Tevatron an excellent place to study charm and bottom physics. This allows for a rich program of spectroscopy, CP parameter measurements, and searches for new physics.
Date: October 13, 2003
Creator: Cranshaw, J.
System: The UNT Digital Library
Adapting SAM for CDF (open access)

Adapting SAM for CDF

The CDF and D0 experiments probe the high-energy frontier and as they do so have accumulated hundreds of Terabytes of data on the way to petabytes of data over the next two years. The experiments have made a commitment to use the developing Grid based on the SAM system to handle these data. The D0 SAM has been extended for use in CDF as common patterns of design emerged to meet the similar requirements of these experiments. The process by which the merger was achieved is explained with particular emphasis on lessons learned concerning the database design patterns plus realization of the use cases.
Date: October 13, 2003
Creator: Bonham, D.; Garzoglio, G.; Herber, R.; Kowalkowski, J.; Litvintsev, D.; Lueking, L. et al.
System: The UNT Digital Library
WInd-and-react Bi-2212 coil development for accelerator magnets (open access)

WInd-and-react Bi-2212 coil development for accelerator magnets

Sub-scale coils are being manufactured and tested at Lawrence Berkeley National Laboratory in order to develop wind-and-react Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub x} (Bi-2212) magnet technology for future graded accelerator magnet use. Previous Bi-2212 coils showed significant leakage of the conductors core constituents to the environment, which can occur during the partial melt reaction around 890 C in pure oxygen. The main origin of the observed leakage is intrinsic leakage of the wires, and the issue is therefore being addressed at the wire manufacturing level. We report on further compatibility studies, and the performance of new sub-scale coils that were manufactured using improved conductors. These coils exhibit significantly reduced leakage, and carry currents that are about 70% of the witness wire critical current (I{sub c}). The coils demonstrate, for the first time, the feasibility of round wire Bi-2212 conductors for accelerator magnet technology use. Successful high temperature superconductor coil technology will enable the manufacture of graded accelerator magnets that can surpass the, already closely approached, intrinsic magnetic field limitations of Nb-based superconducting magnets.
Date: October 13, 2009
Creator: Godeke, A.; Acosta, P.; Cheng, D.; Dietderich, D. R.; Mentink, M. G. T.; Prestemon, S. O. et al.
System: The UNT Digital Library
Performance and Aging Studies of BaBar Resistive Plate Chambers (open access)

Performance and Aging Studies of BaBar Resistive Plate Chambers

The BaBar detector is currently operating nearly 200 Resistive Plate Chambers (RPCs), constructed as part of an upgrade of the forward endcap muon detector in 2002. Although the average RPC efficiency remains high, numerous changes in the RPC performance (increased currents and rates) have been observed. A few of the highest rate RPCs have suffered efficiency losses of more than 15%. Several types of efficiency loss have been observed. Tests with humidified gas have shown that some of the lost efficiency is recoverable. However, efficiency losses in the highest rate regions have not yet improved with humid gases.
Date: October 13, 2006
Creator: Band, H. R.; Hollar, J.; Tan, P.; Anulli, F.; Baldini, R.; Calcaterra, A. et al.
System: The UNT Digital Library
The Crisis in Radiochemistry and Nuclear Chemistry Education (open access)

The Crisis in Radiochemistry and Nuclear Chemistry Education

A brief summary of the current status of radiochemistry and nuclear chemistry in the U. S. and abroad will be given. Current and future needs for scientists in these fields, especially in the U. S., will be discussed. Challenges that must be met in order to reverse the ''catastrophic'' downward trend in the numbers of students, faculty, and university programs in radiochemistry and nuclear chemistry will be considered, and some potential ways to reinvigorate and expand relevant university research and educational programs will be suggested.
Date: October 13, 2005
Creator: Hoffman, D C
System: The UNT Digital Library
Kinetics of helium bubble formation in nuclear materials (open access)

Kinetics of helium bubble formation in nuclear materials

The formation and growth of helium bubbles due to self-irradiation in plutonium has been modeled by a discrete kinetic equations for the number densities of bubbles having k atoms. Analysis of these equations shows that the bubble size distribution function can be approximated by a composite of: (1) the solution of partial differential equations describing the continuum limit of the theory but corrected to take into account the effects of discreteness, and (2) a local expansion about the advancing leading edge of the distribution function in size space. Both approximations contribute to the memory term in a close integrodifferential equation for the monomer concentration of single helium atoms. The present theory is compared to the numerical solution of the full kinetic model and to previous approximation of Schaldach and Wolfer involving a truncated system of moment equations.
Date: October 13, 2005
Creator: Bonilla, L L; Carpio, A; Neu, J C & Wolfer, W G
System: The UNT Digital Library
Instrumentation Standard Architectures for Future High Availability Control Systems (open access)

Instrumentation Standard Architectures for Future High Availability Control Systems

Architectures for next-generation modular instrumentation standards should aim to meet a requirement of High Availability, or robustness against system failure. This is particularly important for experiments both large and small mounted on production accelerators and light sources. New standards should be based on architectures that (1) are modular in both hardware and software for ease in repair and upgrade; (2) include inherent redundancy at internal module, module assembly and system levels; (3) include modern high speed serial inter-module communications with robust noise-immune protocols; and (4) include highly intelligent diagnostics and board-management subsystems that can predict impending failure and invoke evasive strategies. The simple design principles lead to fail-soft systems that can be applied to any type of electronics system, from modular instruments to large power supplies to pulsed power modulators to entire accelerator systems. The existing standards in use are briefly reviewed and compared against a new commercial standard which suggests a powerful model for future laboratory standard developments. The past successes of undertaking such projects through inter-laboratory engineering-physics collaborations will be briefly summarized.
Date: October 13, 2005
Creator: Larsen, R. S.
System: The UNT Digital Library
A fast, flexible algorithm for calculating correlations in Fluorescence Correlation Spectroscopy (open access)

A fast, flexible algorithm for calculating correlations in Fluorescence Correlation Spectroscopy

A new algorithm is introduced for computing correlations of photon arrival time data acquired in single-molecule fluorescence spectroscopy and fluorescence correlation spectroscopy (FCS). The correlation is first rewritten as a counting operation on photon pairs. For each photon, the contribution to the correlation function for each subsequent photon is calculated for arbitrary bin spacings of the correlation time lag. By retaining the bin positions in the photon sequence after each photon, the correlation can be performed efficiently. Example correlations for simulations of FCS experiments are shown, with comparable execution speed to the commonly used multiple-tau correlation technique. Also, wide bin spacings are possible that allow for real-time software calculation of correlations even for high count rates ({approx}350 kHz). The flexibility and broad applicability of the algorithm is demonstrated using results from single molecule photon antibunching experiments.
Date: October 13, 2005
Creator: Laurence, T; Fore, S & Huser, T
System: The UNT Digital Library
Hadron Spectroscopy and Wavefunctions in QCD and the AdS/CFT Correspondence (open access)

Hadron Spectroscopy and Wavefunctions in QCD and the AdS/CFT Correspondence

The AdS/CFT correspondence has led to important insights into the properties of quantum chromodynamics even though QCD is a broken conformal theory. We have recently shown how a holographic model based on a truncated AdS space can be used to obtain the hadronic spectrum of light q{bar q}, qqq and gg bound states. Specific hadrons are identified by the correspondence of string modes with the dimension of the interpolating operator of the hadron's valence Fock state, including orbital angular momentum excitations. The predicted mass spectrum is linear M {proportional_to} L at high orbital angular momentum, in contrast to the quadratic dependence M{sup 2} {proportional_to} L found in the description of spinning strings. Since only one parameter, the QCD scale LQCD, is introduced, the agreement with the pattern of physical states is remarkable. In particular, the ratio of D to nucleon trajectories is determined by the ratio of zeros of Bessel functions. The light-front quantization of gauge theories in light-cone gauge provides a frame-independent wavefunction representation of relativistic bound states, simple forms for current matrix elements, explicit unitarity, and a trivial vacuum. The light-front Fock-state wavefunctions encode the bound state properties of hadrons in terms of their quark and gluon degrees …
Date: October 13, 2005
Creator: Brodsky, Stanley J.; de Teramond, Guy F. & U., /SLAC /Costa Rica
System: The UNT Digital Library
The Madden-Julian Oscillation in ECHAM4 Coupled and Uncoupled GCMs (open access)

The Madden-Julian Oscillation in ECHAM4 Coupled and Uncoupled GCMs

The Madden-Julian Oscillation (MJO) dominates tropical variability on timescales of 30-70 days. During the boreal winter/spring it is manifested as an eastward propagating disturbance, with a strong convective signature over the eastern hemisphere. The space-time structure of the MJO is analyzed using simulations with the ECHAM4 atmospheric general circulation model run with observed monthly mean sea-surface temperatures, and coupled to three different ocean models. The coherence of the eastward propagation of MJO convection is sensitive to the ocean model to which ECHAM4 is coupled. For ECHAM4/OPYC and ECHO-G, models for which {approx}100 years of daily data is available, Monte Carlo sampling indicates that their metrics of eastward propagation are different at the 1% significance level. The flux-adjusted coupled simulations, ECHAM4/OPYC and ECHO-G, maintain a more realistic mean-state, and have a more realistic MJO simulation than the non-adjusted SINTEX coupled runs. The SINTEX model exhibits a cold bias in Indian Ocean and tropical West Pacific Ocean sea-surface temperature of {approx}0.5 C. This cold bias affects the distribution of time-mean convection over the tropical Eastern Hemisphere. Furthermore, the eastward propagation of MJO convection in this model is not as coherent as in the two models that used flux adjustment or compared to …
Date: October 13, 2004
Creator: Sperber, K R; Gualdi, S.; Legutke, S & Gayler, V
System: The UNT Digital Library
GEOCHRONOLOGY AND FLUID-ROCK INTERACTION ASSOCIATED WITH THE NOPAL I URANIUM DEPOSIT, PENA BLANCA, MEXICO (open access)

GEOCHRONOLOGY AND FLUID-ROCK INTERACTION ASSOCIATED WITH THE NOPAL I URANIUM DEPOSIT, PENA BLANCA, MEXICO

The objectives of this report are: (1) Establish chronology of uranium minerals; (2) Characterize fluids; and (3) Relate ages to geological tectonic events.
Date: October 13, 2005
Creator: Fayek, M.; Goodell, P.C.; Ren, M.; Riciputi, L.R.; Simmons, A.; Utsunomiya, S. et al.
System: The UNT Digital Library
Experimental Benchmarking of Pu Electronic Structure (open access)

Experimental Benchmarking of Pu Electronic Structure

The standard method to determine the band structure of a condensed phase material is to (1) obtain a single crystal with a well defined surface and (2) map the bands with angle resolved photoelectron spectroscopy (occupied or valence bands) and inverse photoelectron spectroscopy (unoccupied or conduction bands). Unfortunately, in the case of Pu, the single crystals of Pu are either nonexistent, very small and/or having poorly defined surfaces. Furthermore, effects such as electron correlation and a large spin-orbit splitting in the 5f states have further complicated the situation. Thus, we have embarked upon the utilization of unorthodox electron spectroscopies, to circumvent the problems caused by the absence of large single crystals of Pu with well-defined surfaces. Our approach includes the techniques of resonant photoelectron spectroscopy [1], x-ray absorption spectroscopy [1,2,3,4], electron energy loss spectroscopy [2,3,4], Fano Effect measurements [5], and Bremstrahlung Isochromat Spectroscopy [6], including the utilization of micro-focused beams to probe single-crystallite regions of polycrystalline Pu samples. [2,3,6]
Date: October 13, 2005
Creator: Tobin, J. G.; Moore, K. T.; Chung, B. W.; Wall, M. A.; Schwartz, A. J.; Ebbinghaus, B. B. et al.
System: The UNT Digital Library
Computing Criticality of Lines in Power Systems (open access)

Computing Criticality of Lines in Power Systems

We propose a computationally efficient method based onnonlinear optimization to identify critical lines, failure of which cancause severe blackouts. Our method computes criticality measure for alllines at a time, as opposed to detecting a single vulnerability,providing a global view of the system. This information on criticality oflines can be used to identify multiple contingencies by selectivelyexploring multiple combinations of broken lines. The effectiveness of ourmethod is demonstrated on the IEEE 30 and 118 bus systems, where we canvery quickly detect the most critical lines in the system and identifysevere multiple contingencies.
Date: October 13, 2006
Creator: Pinar, Ali; Reichert, Adam & Lesieutre, Bernard
System: The UNT Digital Library