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Genetically Engineered Crops: Agencies Are Proposing Changes to Improve Oversight, but Could Take Additional Steps to Enhance Coordination and Monitoring (open access)

Genetically Engineered Crops: Agencies Are Proposing Changes to Improve Oversight, but Could Take Additional Steps to Enhance Coordination and Monitoring

A letter report issued by the Government Accountability Office with an abstract that begins "Genetically engineered (GE) crops--including crops engineered to resist pests or tolerate herbicides--are widespread in the United States and around the world. Taking direction from the 1986 Coordinated Framework for Regulation of Biotechnology, the U.S. Department of Agriculture (USDA), Environmental Protection Agency (EPA), and Food and Drug Administration (FDA) regulate GE crops to ensure that they are safe. The unauthorized mixing of some GE crops with non-GE crops has caused controversy and financial harm. GAO examined (1) unauthorized releases of GE crops, (2) coordination among the three agencies, and (3) additional actions they have proposed to improve oversight. GAO gathered data from agencies and stakeholders; used criteria from prior GAO work to assess coordination; and reviewed agency proposals."
Date: November 5, 2008
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Single-cycle nonlinear optics (open access)

Single-cycle nonlinear optics

Nonlinear optics plays a central role in the advancement of optical science and laser-based technologies. We report on the confinement of the nonlinear interaction of light with matter to a single wave cycle and demonstrate its utility for time-resolved and strong-field science. The electric field of 3.3-femtosecond, 0.72-micron laser pulses with a controlled and measured waveform ionizes atoms near the crests of the central wave cycle, with ionization being virtually switched off outside this interval. Isolated sub-100-attosecond pulses of extreme ultraviolet light (photon energy {approx} 80 electron volts), containing {approx} 0.5 nanojoule of energy, emerge from the interaction with a conversion efficiency of {approx} 10{sup -6}. These tools enable the study of the precision control of electron motion with light fields and electron-electron interactions with a resolution approaching the atomic unit of time ({approx} 24 attoseconds).
Date: November 5, 2008
Creator: Max-Planck-Institut fur Quantenoptik
Object Type: Article
System: The UNT Digital Library
Fundamental Investigations of Nanoscale Phenomena in Beam-Assisted Nucleation, Growth and Surface Smoothing, Using in situ LEEM (open access)

Fundamental Investigations of Nanoscale Phenomena in Beam-Assisted Nucleation, Growth and Surface Smoothing, Using in situ LEEM

The purposes for which this grant was provided were specifically (1) to construct a tandem instrument that combined a low energy electron microscope (LEEM) with an ion beam source capably of irradiating a sample during observation of the surface using LEEM; and (2) to employ the new machine to whatever degree possible to observe the evolution of clean crystal surfaces during ion beam irradiation. A principal motivation was to investigate the fundamental behavior of radiation damage under circumstances for which the damage can be observed directly in real time as it occurs. A second main motivation was to create tunable perturbations of the defect (adatom and advacancy) equilibrium on clean crystal planes and in this way explore the fundamental kinetics of surface behavior that enters into numerous phenomena of interest to DOE including surface erosion, catalysis, and the damage to crystals caused by impacts of energetic particles. The funding has been employed to successfully pursue all the original goals, and additional opportunities that developed as a result of discoveries made in this research.
Date: November 5, 2008
Creator: Flynn, Colin P.
Object Type: Text
System: The UNT Digital Library
Search for Invisible Decays of a Light Scalar in Radiative Transitions Y(3S)->gamma A0 (open access)

Search for Invisible Decays of a Light Scalar in Radiative Transitions Y(3S)->gamma A0

We search for a light scalar particle produced in single-photon decays of the {Upsilon}(3S) resonance through the process {Upsilon}(3S) {yields} {gamma} + A{sup 0}, A{sup 0} {yields} invisible. Such an object appears in Next-to-Minimal Supersymmetric extensions of the Standard Model, where a light CP-odd Higgs boson naturally couples strongly to b-quarks. If, in addition, there exists a light, stable neutralino, decays of A{sup 0} could be preferentially to an invisible final state. We search for events with a single high-energy photon and a large missing mass, consistent with a 2-body decay of {Upsilon}(3S). We find no evidence for such processes in a sample of 122 x 10{sup 6} {Upsilon}(3S) decays collected by the BABAR collaboration at the PEP-II B-factory, and set 90% C.L. upper limits on the branching fraction {Beta}({Upsilon}(3S) {yields} {gamma}A{sup 0}) x {Beta}(A{sup 0} {yields} invisible) at (0.7-31) x 10{sup -6} in the mass range m{sub A{sup 0}} {le} 7.8 GeV. The results are preliminary.
Date: November 5, 2008
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Holographic Systematics of D-brane Inflation (open access)

Holographic Systematics of D-brane Inflation

We provide a systematic treatment of possible corrections to the inflaton potential for D-brane inflation in the warped deformed conifold. We consider the D3-brane potential in the presence of the most general possible corrections to the throat geometry sourced by coupling to the bulk of a compact Calabi-Yau space. This corresponds to the potential on the Coulomb branch of the dual gauge theory, in the presence of arbitrary perturbations of the Lagrangian. The leading contributions arise from perturbations by the most relevant operators that do not destroy the throat geometry. We find a generic contribution from a non-chiral operator of dimension {Delta} = 2 associated with a global symmetry current, resulting in a negative contribution to the inflaton mass-squared. If the Calabi-Yau preserves certain discrete symmetries, this is the dominant correction to the inflaton potential, and fine-tuning of the inflaton mass is possible. In the absence of such discrete symmetries, the dominant contribution comes from a chiral operator with {Delta} = 3/2, corresponding to a {phi}{sup 3/2} term in the inflaton potential. The resulting inflationary models are phenomenologically identical to the inflection point scenarios arising from specific D7-brane embeddings, but occur under far more general circumstances. Our strategy extends immediately …
Date: November 5, 2008
Creator: Baumann, Daniel; /Harvard U., Phys. Dept. /Princeton U.; Dymarsky, Anatoly; /Stanford U., Phys. Dept.; Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC et al.
Object Type: Article
System: The UNT Digital Library
Interface Structure and Transport of Complex Oxide Junctions (open access)

Interface Structure and Transport of Complex Oxide Junctions

The interface structure and magnetism of hybrid magnetic tunnel junction-spin filter devices have been investigated and correlated with their transport properties. Magnetic tunnel junctions made of a spinel NiMn2O4 tunnel barrier sandwiched by theoretically predicted half-metallic electrodes, perovskite La0.7Sr0.3MnO3 and spinel Fe3O4, exhibit very high crystalline quality as observed by transmission electron microscopy. Structurally abrupt interfaces allow for the distinct magnetic switching of the electrodes as well as large junction magnetoresistance. The change in the magnetic anisotropy observed at the spinel-spinel interface is indicative of a thin interdiffused magnetically soft interfacial layer. The strong exchange coupling at this interface allows for low background magnetoresistance, and a spin-filter effect with when the barrier is ferrimagnetic.
Date: November 5, 2008
Creator: Nelson-Cheeseman, B.B.; Wong, F.; Chopdekar, R.V.; Chi, M.; Arenholz, E.; Browning, N.D et al.
Object Type: Article
System: The UNT Digital Library
Measurement of the Branching Fractions of Bbar -> D** l^- nubar_l Decays in Events Tagged by a Fully Reconstructed B Meson (open access)

Measurement of the Branching Fractions of Bbar -> D** l^- nubar_l Decays in Events Tagged by a Fully Reconstructed B Meson

We report a measurement of the branching fractions of {bar B} {yields} D** {ell}{sup -}{bar {nu}}{sub {ell}} decays based on 417 fb{sup -1} of data collected at the {Upsilon}(4S) resonance with the BABAR detector at the PEP-II e{sup +}e{sup -} storage rings. Events are selected by fully reconstructing one of the B mesons in a hadronic decay mode. A fit to the invariant mass differences m(D{sup (*)})-m(D{sup (*)}) is performed to extract the signal yields of the different D** states. We observe the {bar B} {yields} D**{ell}{sup -}{bar {nu}}{sub {ell}} decay modes corresponding to the four D** states predicted by Heavy Quark Symmetry with a significance greater than six standard deviations including systematic uncertainties.
Date: November 5, 2008
Creator: Aubert, Bernard; Bona, M.; Karyotakis, Y.; Lees, J. P.; Poireau, V.; Prencipe, E. et al.
Object Type: Article
System: The UNT Digital Library
TECHNICAL EVALUATION OF THE INTERACTION OF GROUNDWATER WITH THE COLUMBIA RIVER AT THE DEPARTMENT OF ENERGY HANFORD SITE 100-D AREA (open access)

TECHNICAL EVALUATION OF THE INTERACTION OF GROUNDWATER WITH THE COLUMBIA RIVER AT THE DEPARTMENT OF ENERGY HANFORD SITE 100-D AREA

Groundwater beneath much of Hanford's 100 Areas is contaminated with hexavalent chromium (Cr{sup +6}) as a consequence of treating reactor cooling water to prevent corrosion. Several treatment systems are in place to remove Cr{sup +6} from the groundwater; however, these systems currently do not reduce Cr{sup +6} to concentrations below aquatic standards. Of concern is the transport of Cr{sup +6} to areas within the channel of the river, as sensitive species inhabit the river and its associated transition zone. The aquatic standard for Cr{sup +6} is currently 11 ug/l under the Record of Decision (ROD) for Interim Action and Department of Energy (DOE) currently plans to pursue remediation of the groundwater to achieve the 11 ug/l standard. Because the compliance wells used to monitor the current remediation systems are located some distance from the river, they may not provide an accurate indication of Cr{sup +6} concentrations in the water that reaches the riverbed. In addition, because salmon spawning areas are considered a high priority for protection from Hanford contaminants, it would be advantageous to understand (1) to what extent Cr{sup +6} discharged to the near-shore or river ecosystems is diluted or attenuated and (2) mechanisms that could mitigate the exposure …
Date: November 5, 2008
Creator: SW, PETERSEN
Object Type: Report
System: The UNT Digital Library
F-AREA PUMP TANK 1 MIXING ANALYSIS (open access)

F-AREA PUMP TANK 1 MIXING ANALYSIS

The F-area pump tanks are used to transfer supernate, sludge, and other materials. In any transfer, the solution must stay well mixed without allowing particulate matter to settle out of the liquid and, thus, accumulate in the bottom of the pump tank. Recently, the pulse jet mixing in F-area Pump Tank 1 (FPT1) has been decommissioned. An analysis of the liquid transfer through FPT1 has been performed using computational fluid dynamics (CFD) methods to assess whether or not the velocities throughout the tank will remain high enough to keep all particulate suspended using only transfer and recirculation pumps. The following paragraph is an abbreviated synopsis of the transfer procedure for FPT1 [1, 2]. Prior to a transfer, FPT1 begins to be filled with inhibited water through the inlet transfer line (TI). When the tank liquid level reaches 52.5 inches above the absolute tank bottom, the recirculation pump (RI and RO) is activated. At a tank liquid level of 72.5 inches above the absolute tank bottom, the outlet transfer line (TO) is activated to reduce the liquid level in FPT1 and transfer inhibited water to H-area Pump Tank 7 (HPT7). The liquid level is reduced down to 39.5 inches, with an …
Date: November 5, 2008
Creator: Tamburello, D; Richard Dimenna, R & Si Lee, S
Object Type: Report
System: The UNT Digital Library
Magnetic Detachment and Plume Control in Escaping Magnetized Plasma (open access)

Magnetic Detachment and Plume Control in Escaping Magnetized Plasma

The model of two-fluid, axisymmetric, ambipolar magnetized plasma detachment from thruster guide fields is extended to include plasmas with non-zero injection angular velocity profiles. Certain plasma injection angular velocity profiles are shown to narrow the plasma plume, thereby increasing exhaust efficiency. As an example, we consider a magnetic guide field arising from a simple current ring and demonstrate plasma injection schemes that more than double the fraction of useful exhaust aperture area, more than halve the exhaust plume angle, and enhance magnetized plasma detachment.
Date: November 5, 2008
Creator: Fisch, P. F. Schmit and N. J.
Object Type: Article
System: The UNT Digital Library
Gravity Duals of Lifshitz-Like Fixed Points (open access)

Gravity Duals of Lifshitz-Like Fixed Points

We find candidate macroscopic gravity duals for scale-invariant but non-Lorentz invariant fixed points, which do not have particle number as a conserved quantity. We compute two-point correlation functions which exhibit novel behavior relative to their AdS counterparts, and find holographic renormalization group flows to conformal field theories. Our theories are characterized by a dynamical critical exponent z, which governs the anisotropy between spatial and temporal scaling t {yields} {lambda}{sup z}t, x {yields} {lambda}x; we focus on the case with z = 2. Such theories describe multicritical points in certain magnetic materials and liquid crystals, and have been shown to arise at quantum critical points in toy models of the cuprate superconductors. This work can be considered a small step towards making useful dual descriptions of such critical points.
Date: November 5, 2008
Creator: Kachru, Shamit; /Stanford U., Phys. Dept. /SLAC; Liu, Xiao; Phys., /Perimeter Inst. Theor.; Mulligan, Michael & /Stanford U., Phys. Dept. /SLAC
Object Type: Article
System: The UNT Digital Library
Magnetic Detachment and Plume Control in Escaping Magnetized Plasma (open access)

Magnetic Detachment and Plume Control in Escaping Magnetized Plasma

The model of two-fluid, axisymmetric, ambipolar magnetized plasma detachment from thruster guide fields is extended to include plasmas with non-zero injection angular velocity profiles. Certain plasma injection angular velocity profiles are shown to narrow the plasma plume, thereby increasing exhaust efficiency. As an example, we consider a magnetic guide field arising from a simple current ring and demonstrate plasma injection schemes that more than double the fraction of useful exhaust aperture area, more than halve the exhaust plume angle, and enhance magnetized plasma detachment.
Date: November 5, 2008
Creator: Fisch, P. F. Schmit and N. J.
Object Type: Report
System: The UNT Digital Library
Measurement of the Color-Suppressed B0->D(*)0 pi0 /omega/eta/eta Prime Branching Fractions (open access)

Measurement of the Color-Suppressed B0->D(*)0 pi0 /omega/eta/eta Prime Branching Fractions

The authors report results on the branching fraction (BF) measurement of the color-suppressed decays {bar B}{sup 0} {yields} D{sup 0}{pi}{sup 0}, D*{sup 0}{pi}{sup 0}, D{sup 0}{eta}, D*{sup 0}{eta}, D{sup 0}{omega}, D*{sup 0}{omega}, D{sup 0}{eta}{prime}, and D*{sup 0}{eta}{prime}. They measure the branching fractions BF(D{sup 0}{pi}{sup 0}) = (2.78 {+-} 0.08 {+-} 0.20) x 10{sup -4}, BF(D*{sup 0}{pi}{sup 0}) = (1.78 {+-} 0.13 {+-} 0.23) x 10{sup -4}, BF(D{sup 0}{eta}) = (2.41 {+-} 0.09 {+-} 0.17) x 10{sup -4}, BF(D*{sup 0}{eta}) = (2.32 {+-} 0.13 {+-} 0.22) x 10{sup -4}, BF(D{sup 0}{omega}) = (2.77 {+-} 0.13 {+-} 0.22) x 10{sup -4}, BF(D*{sup 0}{omega}) = (4.44 {+-} 0.23 {+-} 0.61) x 10{sup -4}, BF(D{sup 0}{eta}{prime}) = (1.38 {+-} 0.12 {+-} 0.22) x 10{sup -4} and BF(D*{sup 0}{eta}{prime}) = (1.29 {+-} 0.23 {+-} 0.23) x 10{sup -4}, where the first uncertainty is statistical and the second is systematic. The result is based on a sample of (454 {+-} 5) x 10{sup 6} B{bar B} pairs collected at the {Upsilon}(4S) resonance from 1999 to 2007, with the BABAR detector at the PEP-II storage rings at the Stanford Linear Accelerator Center. The measurements are compared to theoretical predictions by factorization, SCET and pQCD. The presence of …
Date: November 5, 2008
Creator: Prudent, X
Object Type: Article
System: The UNT Digital Library
Far-from-equilibrium measurements of thermodynamic length (open access)

Far-from-equilibrium measurements of thermodynamic length

Thermodynamic length is a path function that generalizes the notion of length to the surface of thermodynamic states. Here, we show how to measure thermodynamic length in far-from-equilibrium experiments using the work fluctuation relations. For these microscopic systems, it proves necessary to define the thermodynamic length in terms of the Fisher information. Consequently, the thermodynamic length can be directly related to the magnitude of fluctuations about equilibrium. The work fluctuation relations link the work and the free energy change during an external perturbation on a system. We use this result to determine equilibrium averages at intermediate points of the protocol in which the system is out-of-equilibrium. This allows us to extend Bennett's method to determine the potential of mean force, as well as the thermodynamic length, in single molecule experiments.
Date: November 5, 2008
Creator: Feng, Edward H. & Crooks, Gavin E.
Object Type: Article
System: The UNT Digital Library
Full Fuel-Cycle Comparison of Forklift Propulsion Systems.A (open access)

Full Fuel-Cycle Comparison of Forklift Propulsion Systems.A

Hydrogen has received considerable attention as an alternative to fossil fuels. The U.S. Department of Energy (DOE) investigates the technical and economic feasibility of promising new technologies, such as hydrogen fuel cells. A recent report for DOE identified three near-term markets for fuel cells: (1) Emergency power for state and local emergency response agencies, (2) Forklifts in warehousing and distribution centers, and (3) Airport ground support equipment markets. This report examines forklift propulsion systems and addresses the potential energy and environmental implications of substituting fuel-cell propulsion for existing technologies based on batteries and fossil fuels. Industry data and the Argonne Greenhouse Gases, Regulated Emissions, and Energy Use in Transportation (GREET) model are used to estimate full fuel-cycle emissions and use of primary energy sources, back to the primary feedstocks for fuel production. Also considered are other environmental concerns at work locations. The benefits derived from using fuel-cell propulsion are determined by the sources of electricity and hydrogen. In particular, fuel-cell forklifts using hydrogen made from the reforming of natural gas had lower impacts than those using hydrogen from electrolysis.
Date: November 5, 2008
Creator: Gaines, L. L.; Elgowainy, A.; Wang, M. Q. & Systems, Energy
Object Type: Report
System: The UNT Digital Library
Contraints on New Physics in MFV models: a model-independent analysis of \DeltaF=1 processes (open access)

Contraints on New Physics in MFV models: a model-independent analysis of \DeltaF=1 processes

We analyze the constraints on dimension-six {Delta}F = 1 effective operators in models respecting the MFV hypothesis, both in the one-Higgs doublet case and in the two-Higgs doublet scenario with large tan {beta}. The constraints are derived mainly from the b {yields} s inclusive observables measured at the B factories. The implications of these bounds in view of improved measurements in exclusive and inclusive observables in b {yields} s{ell}{sup +}{ell}{sup -} and s {yields} d{nu}{bar {nu}} transitions are discussed.
Date: November 5, 2008
Creator: Hurth, Tobias; /SLAC, /CERN; Isidori, Gino; /Pisa, Scuola Normale Superiore /INFN, Pisa /Frascati; Kamenik, Jernej F.; /Frascati /Stefan Inst., Ljubljana et al.
Object Type: Article
System: The UNT Digital Library
Results of groundwater monitoring at Everest, Kansas, in April 2008. (open access)

Results of groundwater monitoring at Everest, Kansas, in April 2008.

On September 7, 2005, the Commodity Credit Corporation of the U.S. Department of Agriculture (CCC/USDA) presented a Scoping Memo (Argonne 2005) for preliminary consideration by the Kansas Department of Health and Environment (KDHE), suggesting possible remedial options for the carbon tetrachloride contamination in groundwater at Everest, Kansas. The suggested approaches were discussed by representatives of the KDHE, the CCC/USDA, and Argonne at the KDHE office in Topeka on September 8-9, 2005, along with other technical and logistic issues related to the Everest site. In response to these discussions, the KDHE recommended (KDHE 2005) evaluation of several remedial processes, either alone or in combination, as part of a Corrective Action Study (CAS) for Everest. The primary remedial processes suggested by the KDHE were the following: Hydraulic control by groundwater extraction with aboveground treatment; Air sparging (AS) coupled with soil vapor extraction (SVE) in large-diameter boreholes (LDBs); and Phytoremediation. As a further outcome of the 2005 meeting and as a precursor to development of a possible CAS, the CCC/USDA completed the following supplemental investigations at Everest to address several specific technical concerns discussed with the KDHE: (1) Construction of interpretive cross sections at strategic locations selected by the KDHE along the main …
Date: November 5, 2008
Creator: LaFreniere, L. M.
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 39, No. 474, Ed. 1 Wednesday, November 5, 2008 (open access)

Greensheet (Houston, Tex.), Vol. 39, No. 474, Ed. 1 Wednesday, November 5, 2008

Free weekly newspaper that includes business and classified advertising.
Date: November 5, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Optimist (Abilene, Tex.), Vol. 97, No. 21, Ed. 1 Wednesday, November 5, 2008 (open access)

The Optimist (Abilene, Tex.), Vol. 97, No. 21, Ed. 1 Wednesday, November 5, 2008

Bi-weekly student newspaper from Abilene Christian University in Abilene, Texas that includes local, state and campus news along with advertising.
Date: November 5, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean Herald (Rusk, Tex.), Vol. 159, No. 37, Ed. 1 Wednesday, November 5, 2008 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 159, No. 37, Ed. 1 Wednesday, November 5, 2008

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: November 5, 2008
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
North Texas Daily (Denton, Tex.), Vol. 92, No. 42, Ed. 1 Wednesday, November 5, 2008 (open access)

North Texas Daily (Denton, Tex.), Vol. 92, No. 42, Ed. 1 Wednesday, November 5, 2008

Daily student newspaper from the University of North Texas in Denton, Texas that includes local, state and campus news along with advertising.
Date: November 5, 2008
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Rambler (Fort Worth, Tex.), Vol. 101, No. 9, Ed. 1 Wednesday, November 5, 2008 (open access)

The Rambler (Fort Worth, Tex.), Vol. 101, No. 9, Ed. 1 Wednesday, November 5, 2008

Weekly student newspaper from Texas Wesleyan University in Fort Worth, Texas that includes campus and local news along with advertising.
Date: November 5, 2008
Creator: Nugent, Tiara
Object Type: Newspaper
System: The Portal to Texas History
The Rambler (Fort Worth, Tex.), Vol. 101, No. 9, Ed. 1 Wednesday, November 5, 2008 (open access)

The Rambler (Fort Worth, Tex.), Vol. 101, No. 9, Ed. 1 Wednesday, November 5, 2008

Weekly student newspaper from Texas Wesleyan University in Fort Worth, Texas that includes campus and local news along with advertising.
Date: November 5, 2008
Creator: Garcia, Martin
Object Type: Newspaper
System: The Portal to Texas History
Texas Attorney General Opinion: GA-0679 (open access)

Texas Attorney General Opinion: GA-0679

Document issued by the Office of the Attorney General of Texas in Austin, Texas, providing an interpretation of Texas law. It provides the opinion of the Texas Attorney General, Greg Abbott, regarding a legal question submitted for clarification: Construction of a conflict of interest statue, Government Code section 2054.022(a)(7), which prohibits a board member or executive director of the Department of Information Resources from accepting or receiving "money or another thing of value from an individual, firm, or corporation to whom a contract may be awarded" (RQ-0706-GA).
Date: November 5, 2008
Creator: Texas. Attorney-General's Office.
Object Type: Text
System: The Portal to Texas History