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Fatty acid amide hydrolase and 9-lipoxygenase  modulate cotton seedling growth by ethanolamide  oxylipin levels (open access)

Fatty acid amide hydrolase and 9-lipoxygenase modulate cotton seedling growth by ethanolamide oxylipin levels

Article asserts that polyunsaturated N-acylethanolamines (NAEs) can be hydrolyzed by fatty acid amide hydrolase (FAAH) or oxidized by lipoxygenase (LOX). Altogether, the authors conclude that the growth of cotton seedlings involves fine-tuning of 9-NAE-HOD levels via FAAH-mediated hydrolysis and LOX-mediated production, expanding the mechanistic understanding of plant growth modulation by NAE oxylipins to a perennial crop species.
Date: December 6, 2022
Creator: Gaguancela-Arias, Omar; Aziz, Mina & Chapman, Kent Dean
System: The UNT Digital Library
On the mechanism for plasma hydrogenation of graphene (open access)

On the mechanism for plasma hydrogenation of graphene

This article discusses the mechanism for plasma hydrogenation of graphene.
Date: December 6, 2010
Creator: Jones, Jason D.; Hoffmann, William D.; Jesseph, Aaron V.; Morris, Christopher; Verbeck, Guido F. & Pérez, José M.
System: The UNT Digital Library
Single photon induced symmetry breaking of H2 dissociation (open access)

Single photon induced symmetry breaking of H2 dissociation

H{sub 2}, the smallest and most abundant molecule in the universe, has a perfectly symmetric ground state. What does it take to break this symmetry? Here we show that the inversion symmetry can be broken by absorption of a linearly polarized photon, which itself has inversion symmetry. In particular, the emission of a photoelectron with subsequent dissociation of the remaining H{sub 2}{sup +} fragment shows no symmetry with respect to the ionic H+ and neutral H atomic fragments. This result is the consequence of the entanglement between symmetric and antisymmetric H{sub 2}{sup +} states resulting from autoionization. The mechanisms behind this symmetry breaking are general for all molecules.
Date: December 6, 2006
Creator: Martin, F.; Fernandez, J.; Havermeier, T.; Foucar, L.; Weber, Th.; Kreidi, K. et al.
System: The UNT Digital Library
Houston's Premier Party Diva Lands a Special Toast to Her Philanthropic Efforts Across the Globe (open access)

Houston's Premier Party Diva Lands a Special Toast to Her Philanthropic Efforts Across the Globe

Article about a party held to celebrate Becca Cason Thrash's fundraising efforts.
Date: December 6, 2017
Creator: Hodge, Shelby
System: The UNT Digital Library
Medial thalamic 18-FDG uptake following inescapable shock correlates with subsequent learned helpless behavior (open access)

Medial thalamic 18-FDG uptake following inescapable shock correlates with subsequent learned helpless behavior

The learned helplessness paradigm has been repeatedly shown to correlate with neurobiological aspects of depression in humans. In this model, rodents are exposed inescapable foot-shock in order to reveal susceptibility to escape deficit, defined as 'learned helplessness' (LH). Few methods are available to probe the neurobiological aspects underlying the differences in susceptibility in the living animal, thus far being limited to studies examining regional neurochemical changes with microdialysis. With the widespread implementation of small animal neuroimaging methods, including positron emission tomography (PET), it is now possible to explore the living brain on a systems level to define regional changes that may correlate with vulnerability to stress. In this study, 12 wild type Sprague-Dawley rats were exposed to 40 minutes of inescapable foot-shock followed by metabolic imaging using 2-deoxy-2[{sup 18}F]fluoro-D-glucose (18-FDG) 1 hour later. The escape test was performed on these rats 48 hours later (to accommodate radiotracer decay), where they were given the opportunity to press a lever to shut off the shock. A region of interest (ROI) analysis was used to investigate potential correlations (Pearson Regression Coefficients) between regional 18-FDG uptake following inescapable shock and subsequent learned helpless behavior (time to finish the test; number of successful lever presses …
Date: December 6, 2009
Creator: Mirrione, M. M.; Schulz, D.; Dewey, S. L. & Henn, F. A.
System: The UNT Digital Library
Comprehensive supernate treatment (open access)

Comprehensive supernate treatment

This task involves the recovery of the liquid (supernatant or supernate) portions of Oak Ridge National Laboratory (ORNL) Melton Valley Storage Tank waste in a hot cell and treatment of the supernate to separate and remove the radionuclides. The supernate is utilized in testing various sorbent materials for removing cesium, strontium, and technetium from the highly alkaline, saline solutions. Batch tests are used to evaluate and select the most promising materials for supernate treatment to reduce the amount of waste for final disposal. Once the sorbents have been selected based on the results from the batch tests, small column tests are made to verify the batch data. Additional data from these tests can be used for process design. The sorption tests emphasize evaluation of newly developed sorbents and engineered forms of sorbents. Methods are also evaluated for recovering the radionuclides from the sorbents, including evaluating conditions for eluting ion exchange resins. A final report will summarize the results and compare the results with those of other investigators, along with recommendations for separating and concentrating radionuclides from DOE storage tank supernates at Oak Ridge and other sites. Documentation of the data and the significance of the findings will be compared, and …
Date: December 6, 1996
Creator: Egan, B. Z.; Collins, J. L.; Davidson, D. J.; Anderson, K. K. & Chase, C. W.
System: The UNT Digital Library
Hanford`s spent nuclear fuel retrieval: an agressive agenda (open access)

Hanford`s spent nuclear fuel retrieval: an agressive agenda

Starting December 1997, spent nuclear fuel that has been stored in the K Reactor Fuel Storage Basins will be retrieved over a two year period and repackaged for long term dry storage. The aging and sometimes corroding fuel elements will be recovered and processed using log handled tools and teleoperated manipulator technology. The U.S. Department of Energy (DOE) is committed to this urgent schedule because of the environmental threats to the groundwater and nearby the Columbia River.
Date: December 6, 1996
Creator: Shen, E.J., Westinghouse Hanford
System: The UNT Digital Library
Multi-method characterization of low-level radioactive waste at two Sandia National Laboratories environmental restoration sites (open access)

Multi-method characterization of low-level radioactive waste at two Sandia National Laboratories environmental restoration sites

This paper discusses the application of multiple characterization methods to radioactive wastes generated by the Sandia National Laboratories/New Mexico (SNL/NM) Environmental Restoration (ER) Project during the excavation of buried materials at the Classified Waste Landfill (CWLF) and the Radioactive Waste Landfill (RWL). These waste streams include nuclear weapon components and other refuse that are surface contaminated or contain sealed radioactive sources with unknown radioactivity content. Characterization of radioactive constituents in RWL and CWLF waste has been problematic, due primarily to the lack of documented characterization data prior to burial. A second difficulty derives from the limited information that ER project personnel have about weapons component design and testing that was conducted in the early days of the Cold War. To reduce the uncertainties and achieve the best possible waste characterization, the ER Project has applied both project-specific and industry-standard characterization methods that, in combination, serve to define the types and quantities of radionuclide constituents in the waste. The resulting characterization data have been used to develop waste profiles for meeting disposal site waste acceptance criteria.
Date: December 6, 1999
Creator: Johnson, C.E. Jr.; Galloway, R.B. & Dotson, P.W.
System: The UNT Digital Library
Physics research opportunities with XFEL's. (open access)

Physics research opportunities with XFEL's.

The advent of x-ray Free Electron Lasers will present a number of unique new scientific opportunities. These arise from their special characteristics which include intensely brilliant pulses of x-rays delivered in very short times, complete transverse coherence, and high photon quantum degeneracy, amongst other things. While clearly much thought needs to be given to a detailed quantitative assessment of the feasibility of various experiments using such sources, including methods of dealing with heat loads on beamline optics and radiation damage to samples, there are a number of areas in which one can see new opportunities, and other exciting possibilities about which one might speculate. In this talk the author briefly reviews some of these areas, such as x-ray holography, pump-probe type experiments, correlation spectroscopy and quantum optics experiments with x-rays.
Date: December 6, 1999
Creator: Sinha, S. K.
System: The UNT Digital Library
Feasibility of High Yield / High Gain NIF Capsules (open access)

Feasibility of High Yield / High Gain NIF Capsules

Our original ignition ''point designs'' (circa 1992) for the National Ignition Facility (NIF) were made energetically conservative to provide margin for uncertainties in laser absorption, x-ray conversion efficiency and hohlraum-capsule coupling. Since that time, extensive experiments on Nova and Omega and their related analysis indicate that NIF coupling efficiency may be almost ''as good as we could hope for''. Given close agreement between experiment and theory/modeling, we can credibly explore target enhancements which couple more of NIF's energy to an ignition capsule. We find that 3-4X increases in absorbed capsule energy appear possible, providing a potentially more robust target and {approx}10X increase in capsule yield.
Date: December 6, 1999
Creator: Suter, L.; Rothenberg, J.; Munro, D.; Van Wonterghem, B.; Haan, S. & Lindl, J.
System: The UNT Digital Library
Extreme Load Estimation for Wind Turbines: Issues and Opportunities for Improved Practice (open access)

Extreme Load Estimation for Wind Turbines: Issues and Opportunities for Improved Practice

None
Date: December 6, 2000
Creator: Veers, P. S. & Butterfield, S.
System: The UNT Digital Library
Application of natural radionuclides for determination of tropospheric ozone and aerosol transport. (open access)

Application of natural radionuclides for determination of tropospheric ozone and aerosol transport.

Natural radionuclides have been proposed for use in assessing the transport of ozone and aerosols in the troposphere. For example, {sup 7}Be is known to be produced in the upper troposphere and lower stratosphere by interactions with cosmogenic particles. Beryllium-7 has a 53.28-day half-life and is a gamma emitter that attaches itself to fine particles in the atmosphere once it is formed. Indeed, in tropospheric aerosol samples TBe is typically found in association with aerosol particles that are 0.3 {micro}m in diameter. Some investigators have asserted that ozone from aloft can be transported into rural and urban regions during stratospheric/tropospheric folding events, leading to increased background levels of ozone. During the Texas 2000 Air Quality study, aerosol samples with a 2.5-{micro}m cutoff were collected during 12-hour cycles (day/night) for a 30-day period at the Deer Park, Texas, field site in August-September 2000. To monitor {sup 7}Be levels, high-volume samples were collected on glass fiber filters on Julian dates 225-259. Sample collection was at a field site near a city park, away from any nearby traffic. This site is under routine operation by the Texas Natural Resource Conservation Commission. Instruments operated at this same site during the study period included an …
Date: December 6, 2000
Creator: Gaffney, J. S.; Marley, N. A.; Drayton, P. J. & Orlandini, K. A.
System: The UNT Digital Library
Lifetime Predictions for Elastomers from Accelerated Aging Experiments (open access)

Lifetime Predictions for Elastomers from Accelerated Aging Experiments

None
Date: December 6, 2000
Creator: GILLEN,KENNETH T. & CLOUGH,ROGER LEE
System: The UNT Digital Library
Superposition and Wear-Out Approaches Applied to Polymer Lifetime Prediction (open access)

Superposition and Wear-Out Approaches Applied to Polymer Lifetime Prediction

None
Date: December 6, 2000
Creator: CELINA,MATHEW & GILLEN,KENNETH T.
System: The UNT Digital Library
Structure characteristics of ISD coated conductors. (open access)

Structure characteristics of ISD coated conductors.

None
Date: December 6, 2001
Creator: Tang, Y. L.; Miller, D. J.; Ma, B.; Koritala, R. E. & Balachandran, U.
System: The UNT Digital Library
Pointing Control Design for a High Precision Flight Telescope Using Quantitative Feedback Theory (open access)

Pointing Control Design for a High Precision Flight Telescope Using Quantitative Feedback Theory

None
Date: December 6, 2000
Creator: Bentley, Anthony E.
System: The UNT Digital Library
Radiation embrittlement studies using anomalous small-angle x-ray scattering (open access)

Radiation embrittlement studies using anomalous small-angle x-ray scattering

Anomalous small angle x-ray scattering (ASAXS) was performed on an Fe-O.9 wt.% Cu-1.0 wt.% Mn alloy subjected to annealing or electron irradiation. ASAXS takes advantage of natural variations in the atomic scattering factor which exist at energies very near an element's x-ray absorption edge. By performing systematic SAXS experiments at energies near these absorption edges of the constituent alloy elements it is possible to vary the contrast of scattering centers containing the elements and in doing so quantify scatterer composition. The results of such an analysis for the samples in this work indicate the presence of Cu-rich, Cu{sub 85}Mn{sub 15} precipitates in the alloy. By applying the maximum entropy technique to the scattering data, it was possible to extract size distributions of scattering centers fog the different treatments. The results demonstrate the ability to detect and characterize small (11 {angstrom} radius) scatterers at quite low irradiation damage levels (5x10{sup {minus} 4} displacements per atom).
Date: December 6, 1999
Creator: Alexander, D. E.; Kestel, B. J.; Seifert, S.; Jemian, P. R.; Odette, G. R.; Klingensmith, D. et al.
System: The UNT Digital Library
Performance of amorphous carbon coating in turbocompressor air bearings. (open access)

Performance of amorphous carbon coating in turbocompressor air bearings.

None
Date: December 6, 2001
Creator: Ajayi, O. O.; Woodford, J. B.; Erdemir, A. & Fenske, G. R.
System: The UNT Digital Library
Oxidative Degradation Analysis of HTPB/IPDI Polyurethane Using {sup 17}O and {sup 13}C NMR (open access)

Oxidative Degradation Analysis of HTPB/IPDI Polyurethane Using {sup 17}O and {sup 13}C NMR

None
Date: December 6, 2000
Creator: Harris, D. J. & Assink, R. A.
System: The UNT Digital Library
The Role of Quantum Mechanics in Neutrino Factories. (open access)

The Role of Quantum Mechanics in Neutrino Factories.

A compilation is made of the various ways in which quantum phenomena enter into the design and operation of a neutrino factory. They include production of pions, decay of pions into muons, ionization energy loss of muons in material, scattering and energy straggling of muons in material, polarization of muons, and the decay of muons into neutrinos, and the radiation effect of neutrinos. For each process formulas are presented which cover the basic mechanism. A discussion is presented of the areas of uncertainty and of the experiments, underway and proposed, which will reduce the uncertainty to an acceptable level.
Date: December 6, 2000
Creator: Gallardo, J. C.; Sessler, A. M. & Wurtele, J.
System: The UNT Digital Library
Global Warming: A Science Overview for the A/C Industry (open access)

Global Warming: A Science Overview for the A/C Industry

Fossil fuels (i.e., coal, oil, and natural gas) provide about 85% of the world's energy, sustaining our standard-of-living. They are inexpensive, transportable, safe, and relatively abundant. At the same time, their use contributes to problems such as air quality and acid rain that are being addressed through various control efforts and to the problem of global warming, which is now being considered by governments of the world. This talk will focus on six key aspects of the scientific findings that are leading to proposals for significant limitation of the emissions of fossil-fuel-derived carbon dioxide and limitations on emissions of other greenhouse gases that can influence the global climate, including substances used in the refrigeration and air-conditioning industries.
Date: December 6, 1999
Creator: MacCracken, M.C.
System: The UNT Digital Library
Deactivation of the P, C, and R Reactor Disassembly Basins at the SRS (open access)

Deactivation of the P, C, and R Reactor Disassembly Basins at the SRS

The Facilities Disposition Division (FDD) at the Savannah River Site is engaged in planning the deactivation/closure of three of the site's five reactor disassembly basins. Activities are currently underway at 105-R Disassembly Basin and will continue with the 105-P and 105-C disassembly basins. The basins still contain the cooling and shielding water that was present when operations ceased. Low concentrations of radionuclides are present, with tritium, Cs-137, and Sr-90 being the major contributors. Although there is no evidence that any of the basins have leaked, the 50-year-old facilities will eventually contaminate the surrounding groundwaters. The FDD is pursuing a pro-active solution to close the basins in-place and prevent a release to the groundwater. In-situ ion-exchange is currently underway at the R-Reactor Disassembly Basin to reduce the Cs and Sr concentrations to levels that would allow release of the treated water to previously used on-site cooling ponds. A NEPA Environmental Assessment (EA) is being prepared to propose the preferred closure alternative for each of the three basins. The EA will be the primary mechanism to inform the public and gain stakeholder and regulatory approval.
Date: December 6, 2000
Creator: Pickett, J.B.
System: The UNT Digital Library
Alternative Gate Dielectrics on Semiconductors for MOSFET Device Applications (open access)

Alternative Gate Dielectrics on Semiconductors for MOSFET Device Applications

We have investigated the synthesis and properties of deposited oxides on Si and Ge for use as alternative gate dielectrics in MOSFET applications. The capacitance and leakage current behavior of polycrystalline Y{sub 2}O{sub 3} films synthesized by pulsed-laser deposition is reported. In addition, we also discuss the growth of epitaxial oxide structures. In particular, we have investigated the use of silicide termination for oxide growth on (001) Si using laser-molecular beam epitaxy. In addition, we discuss a novel approach involving the use of hydrogen to eliminate native oxide during initial dielectric oxide nucleation on (001) Ge.
Date: December 6, 1999
Creator: Norton, D. P.; Budai, J. D.; Chisholm, M. F.; Pennycook, S. J.; McKee, R.; Walker, F. et al.
System: The UNT Digital Library
Comparison of the crevice corrosion resistance of Alloys 625 and 22 in concentrated chloride solution from 60 to 95 degrees C (open access)

Comparison of the crevice corrosion resistance of Alloys 625 and 22 in concentrated chloride solution from 60 to 95 degrees C

The effects of electrolyte composition and oxide film age on the crevice corrosion properties of alloys 625 and 22 were studied at temperatures ranging from 60 to 95 C in concentrated chloride electrolytes. Critical potentials were determined using conventional current density thresholds and comparisons were made between 625 and 22 on the basis of these critical potentials. Air aged 22 specimens exhibited the highest resistance to crevice corrosion at 95 C in terms of critical crevice potentials, while freshly polished 22 exhibited the lowest resistance. Studies over the entire, temperature range showed that air aged 22 is more resistant to crevice corrosion than air aged 625 as evidenced by higher critical crevice potentials. As the temperature was lowered from 95 to 8O C, critical crevice potentials for 22 either approached or exceeded experimentally determined Cr (Mo, Ni) transpassive potentials.
Date: December 6, 1999
Creator: Kehler, B. A.; Illevbare, G. O. & Scully, J. R.
System: The UNT Digital Library