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Structural Consideration in Designing Organotin Polyethers to Arrest the Growth of Breast Cancer Cells In Vitro (open access)

Structural Consideration in Designing Organotin Polyethers to Arrest the Growth of Breast Cancer Cells In Vitro

The article looks at antitumor activity using a matched pair of cell lines MDA-MB-231 cells that are estrogen-independent, estrogen receptor negative and MCF-7 cells, a cell line that is estrogen receptor (ER) positive. Those polyethers that contained a O-phenyl unit were able to significantly inhibit the non-estrogen sensitive cell line but were much less effective against the estrogen sensitive cell line; that is, the human breast cancer cell line MDA-MB-231 showed better test results for polymers derived from diols containing the O-phenyl moiety than the breast cancer cell line MCF-7, a well-characterized estrogen receptor positive control cell line.
Date: April 15, 2011
Creator: Carraher, Charles E., Jr.; Roner, Michael R.; Shahi, Kimberly & Barot, Girish
System: The UNT Digital Library
Long-Term Low-Level Arsenic Exposure Is Associated with Poorer Neuropsychological Functioning: A Project FRONTIER Study (open access)

Long-Term Low-Level Arsenic Exposure Is Associated with Poorer Neuropsychological Functioning: A Project FRONTIER Study

Study examines the potential association between current and long-term arsenic exposure and detailed neuropsychological functioning in a sample of rural-dwelling adults and elders.
Date: March 15, 2011
Creator: O'Bryant, Sid E.; Edwards, Melissa; Menon, Chloe V.; Gong, Gordon & Barber, Robert C.
System: The UNT Digital Library
Prompt Energy Distribution of 235U(n,f)gamma at Bombarding Energies of 1 to 20 MeV (open access)

Prompt Energy Distribution of 235U(n,f)gamma at Bombarding Energies of 1 to 20 MeV

None
Date: December 15, 2011
Creator: Kwan, E.; Wu, C. Y.; Haight, R. C.; Lee, H. Y.; Bredeweg, T. A.; Chyzh, A. et al.
System: The UNT Digital Library
A New Method to Generate Dust with Astrophysical Properties (open access)

A New Method to Generate Dust with Astrophysical Properties

None
Date: February 15, 2011
Creator: Hansen, J. F.; Breugel, B.; Bringa, E. M.; Eberly, B.; Graham, G. A.; Remington, B. A. et al.
System: The UNT Digital Library
SIZE EFFECT AND CYLINDER TEST ON SEVERAL COMMERCIAL EXPLOSIVES (open access)

SIZE EFFECT AND CYLINDER TEST ON SEVERAL COMMERCIAL EXPLOSIVES

None
Date: June 15, 2011
Creator: Souers, P C; Lauderbach, L; Moua, K & Garza, R
System: The UNT Digital Library
WCET Tool Challenge 2011: Report (open access)

WCET Tool Challenge 2011: Report

None
Date: June 15, 2011
Creator: Hanxleden, R. v.; Holsti, N.; Lisper, B.; Ploedereder, E.; Wilhelm, R.; Bonenfant, A. et al.
System: The UNT Digital Library
Anomalous transient uplift observed at the Lop Nor, China nuclear test site using satellite radar interferometry time-series analysis (open access)

Anomalous transient uplift observed at the Lop Nor, China nuclear test site using satellite radar interferometry time-series analysis

None
Date: August 15, 2011
Creator: Vincent, P; Buckley, S M; Yang, D & Carle, S F
System: The UNT Digital Library
J/psi suppression at forward rapidity in Au+Au collisions at sqrt(s_NN)=200 GeV (open access)

J/psi suppression at forward rapidity in Au+Au collisions at sqrt(s_NN)=200 GeV

None
Date: November 15, 2011
Creator: Soltz, R A; Glenn, A & Garishvili, I
System: The UNT Digital Library
Recent Developments in Dynamic Transmission Electron Microscopy (open access)

Recent Developments in Dynamic Transmission Electron Microscopy

None
Date: April 15, 2011
Creator: Browning, N D; Bonds, M A; Campbell, G H; Evans, J E; LaGrange, T; Jungjohann, K L et al.
System: The UNT Digital Library
Gold Charge State Distributions in Highly Ionized, Low-Density Beam Plasmas (open access)

Gold Charge State Distributions in Highly Ionized, Low-Density Beam Plasmas

None
Date: June 15, 2011
Creator: May, M. J.; Scofield, J.; Schneider, M.; Wong, K.; Beiersdorfer, P. & Hansen, S. B.
System: The UNT Digital Library
A Piecewise Linear Discontinuous Finite Element Spatial Discretization of the Sn Transport Equation for Polyhedral Grids in 3D Cartesian Geometry (open access)

A Piecewise Linear Discontinuous Finite Element Spatial Discretization of the Sn Transport Equation for Polyhedral Grids in 3D Cartesian Geometry

None
Date: August 15, 2011
Creator: Bailey, T S; Hawkins, W D & Adams, M L
System: The UNT Digital Library
Ultra Low Density and Highly Crosslinked Biocompatible Shape Memory Polyurethane Foams (open access)

Ultra Low Density and Highly Crosslinked Biocompatible Shape Memory Polyurethane Foams

None
Date: September 15, 2011
Creator: Singhal, P.; Rodriguez, J. N.; Small, W., IV; Eagleaston, S.; De Water, J. V.; Maitland, D. J. et al.
System: The UNT Digital Library
Ranking Information in Networks (open access)

Ranking Information in Networks

None
Date: November 15, 2011
Creator: Eliassi-Rad, Tina & Henderson, Keith
System: The UNT Digital Library
Characterization of Uranium Oxyfluoride Particles for Nuclear Safeguards (open access)

Characterization of Uranium Oxyfluoride Particles for Nuclear Safeguards

None
Date: June 15, 2011
Creator: Kips, R.; Kristo, M. J.; Crowhurst, J. & Hutcheon, I. D.
System: The UNT Digital Library
A Population of X-Ray Weak Quasars: PHL 1811 Analogs at High Redshift (open access)

A Population of X-Ray Weak Quasars: PHL 1811 Analogs at High Redshift

This article reports the results from Chandra and XMM-Newton observations of a sample of 10 type 1 quasars selected to have unusual UV emission-line properties similar to those of PHL 1811.
Date: April 15, 2011
Creator: Wu, Jianfeng; Brandt, William Nielsen; Hall, Patrick B.; Gibson, Robert R.; Richards, Gordon T.; Schneider, Donald P. et al.
System: The UNT Digital Library
A Hierarchical Control Architecture for a PEBB-Based ILC Marx Modulator (open access)

A Hierarchical Control Architecture for a PEBB-Based ILC Marx Modulator

The idea of building power conversion systems around Power Electronic Building Blocks (PEBBs) was initiated by the U.S. Office of Naval Research in the mid 1990s. A PEBB-based design approach is advantageous in terms of power density, modularity, reliability, and serviceability. It is obvious that this approach has much appeal for pulsed power conversion including the International Linear Collider (ILC) klystron modulator application. A hierarchical control architecture has the inherent capability to support the integration of PEBBs. This has already been successfully demonstrated in a number of industrial applications in the recent past. This paper outlines the underlying concepts of a hierarchical control architecture for a PEBB-based Marx-topology ILC klystron modulator. The control in PEBB-based power conversion systems can be functionally partitioned into (three) hierarchical layers; system layer, application layer, and PEBB layer. This has been adopted here. Based on such a hierarchical partition, the interfaces are clearly identified and defined and, consequently, are easily characterised. A conceptual design of the hardware manager, executing low-level hardware oriented tasks, is detailed. In addition, the idea of prognostics is briefly discussed.
Date: December 15, 2011
Creator: Macken, K.; Burkhart, C.; Larsen, R.; Nguyen, M. N. & Olsen, J.
System: The UNT Digital Library
Insert Coil Test for HEP High Field Magnets Using YBCO Coated Conductor Tapes (open access)

Insert Coil Test for HEP High Field Magnets Using YBCO Coated Conductor Tapes

The final beam cooling stages of a Muon Collider may require DC solenoid magnets with magnetic fields of 30-50 T. In this paper we present progress in insert coil development using commercially available YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} Coated Conductor. Technological aspects covered in the development, including coil geometry, insulation, manufacturing process and testing are summarized and discussed. Test results of double pancake coils operated in liquid nitrogen and liquid helium are presented and compared with the performance of YBa{sub 2}Cu{sub 3}O{sub 7-{delta}} tape short samples.
Date: June 15, 2011
Creator: Lombardo, V.; Barzi, E.; Turrioni, D. & Zlobin, A. V.
System: The UNT Digital Library
Review of Standard Tau Decays From the B-Factory Experiments (open access)

Review of Standard Tau Decays From the B-Factory Experiments

B-factories have been successfully operating for more than 8 years, providing an unprecedented data sample of e{sup +}e{sup 0} {yields} hadrons events. The BABAR and Belle experiments have in fact already collected over 550 fb{sup -1} and 800 fb{sup -1} respectively at the {Upsilon}(4s) center-of-mass (CM) energy. At this energy, the cross-section for tau production is of the same order of the cross-section for b production: {sigma}(b{bar b}) {approx} 1.1 nb {approx} {sigma}({tau}{sup +}{tau}{sup -}) {approx} 0.9 nb. For this reason, B-factories can now be considered also Tau-factories. A review of the most recent results on standard tau decays from the BABAR and Belle experiments is presented in this article.
Date: November 15, 2011
Creator: Salvatore, F. & /Royal Holloway, U. of London
System: The UNT Digital Library
Unitarity Constraints on Asymmetric Freeze-In (open access)

Unitarity Constraints on Asymmetric Freeze-In

This paper considers unitarity and CPT constraints on asymmetric freeze-in, the use of freeze-in to store baryon number in a dark sector. In this scenario, Sakharov's out of equilibrium condition is satisfied by placing the visible and hidden sectors at different temperatures while a net visible baryon number is produced by storing negative baryon number in a dark sector. It is shown that unitarity and CPT lead to unexpected cancellations. In particular, the transfer of baryon number cancels completely at leading order. This note has shown that if two sectors are in thermal equilibrium with themselves, but not with each other, then the leading effect transferring conserved quantities between the two sectors is of order the the weak coupling connecting them to the third power. When freeze-in is used to produce a net baryon number density, the leading order effect comes from {Omicron}({lambda}{sup 3}) diagrams where the intermediate state that goes on-shell has a different visible baryon number than the final state visible baryon number. Models in which the correct baryon number is generated with freeze-in as the dominant source of abundance, typically require {lambda} {approx}> 10{sup -6} and m{sub bath} {approx}> TeV. m{sub bath} is the mass of the …
Date: August 15, 2011
Creator: Hook, Anson
System: The UNT Digital Library
New Prospects in High Energy Astrophysics (open access)

New Prospects in High Energy Astrophysics

Recent discoveries using TeV, X-ray and radio telescopes as well as Ultra High Energy Cosmic Ray arrays are leading to new insights into longstanding puzzles in high energy astrophysics. Many of these insights come from combining observations throughout the electromagnetic and other spectra as well as evidence assembled from different types of source to propose general principles. Issues discussed in this general overview include methods of accelerating relativistic particles, and amplifying magnetic field, the dynamics of relativistic outflows and the nature of the prime movers that power them. Observational approaches to distinguishing hadronic, leptonic and electromagnetic outflows and emission mechanisms are discussed along with probes of the velocity field and the confinement mechanisms. Observations with GLAST promise to be very prescriptive for addressing these problems.
Date: November 15, 2011
Creator: Blandford, Roger
System: The UNT Digital Library
Built-in and Induced Polarization Across LaAlO3/SrTiO3 Heterojunctions (open access)

Built-in and Induced Polarization Across LaAlO3/SrTiO3 Heterojunctions

Ionic crystals terminated at oppositely charged polar surfaces are inherently unstable and expected to undergo surface reconstructions to maintain electrostatic stability. Essentially, an electric field that arises between oppositely charged atomic planes gives rise to a built-in potential that diverges with thickness. Here we present evidence of such a built-in potential across polar LaAlO{sub 3} thin films grown on SrTiO{sub 3} substrates, a system well known for the electron gas that forms at the interface. By performing tunneling measurements between the electron gas and metallic electrodes on LaAlO{sub 3} we measure a built-in electric field across LaAlO{sub 3} of 80.1 meV/{angstrom}. Additionally, capacitance measurements reveal the presence of an induced dipole moment across the heterostructure. We forsee use of the ionic built-in potential as an additional tuning parameter in both existing and novel device architectures, especially as atomic control of oxide interfaces gains widespread momentum.
Date: August 15, 2011
Creator: Guneeta, Singh-Bhalla
System: The UNT Digital Library
2011 Organometallic Chemistry (July 10-15, 2011, Salve Regina University, Newport, RI) (open access)

2011 Organometallic Chemistry (July 10-15, 2011, Salve Regina University, Newport, RI)

Organometallic chemistry has played and will continue to play a significant role in helping us understand the way bonds are made or broken in the presence of a transition metal complex. Current challenges range from the efficient exploitation of energy resources to the creative use of natural and artificial enzymes. Most of the new advances in the area are due to our extended understanding of processes at a molecular level due to new mechanistic studies, techniques to detect reaction intermediates and theory. The conference will bring the most recent advances in the field including nanocatalysis, surface organometallic chemistry, characterization techniques, new chemical reactivity and theoretical approaches along with applications to organic synthesis and the discovery of new materials. The Conference will bring together a collection of investigators who are at the forefront of their field, and will provide opportunities for junior scientists and graduate students to present their work in poster format and exchange ideas with leaders in the field. Six outstanding posters will be selected for short talks. The collegial atmosphere of this Conference, with programmed discussion sessions as well as opportunities for informal gatherings in the afternoons and evenings, provides an avenue for scientists from different disciplines to …
Date: July 15, 2011
Creator: Bunel, Dr. Emilio
System: The UNT Digital Library
Theory of Two-Magnon Raman Scattering in Iron Pnictides and Chalcogenides (open access)

Theory of Two-Magnon Raman Scattering in Iron Pnictides and Chalcogenides

Although the parent iron-based pnictides and chalcogenides are itinerant antiferromagnets, the use of local moment picture to understand their magnetic properties is still widespread. We study magnetic Raman scattering from a local moment perspective for various quantum spin models proposed for this new class of superconductors. These models vary greatly in the level of magnetic frustration and show a vastly different two-magnon Raman response. Light scattering by two-magnon excitations thus provides a robust and independent measure of the underlying spin interactions. In accord with other recent experiments, our results indicate that the amount of magnetic frustration in these systems may be small.
Date: August 15, 2011
Creator: Chen, C. C.
System: The UNT Digital Library
ADDING REALISM TO NUCLEAR MATERIAL DISSOLVING ANALYSIS (open access)

ADDING REALISM TO NUCLEAR MATERIAL DISSOLVING ANALYSIS

Two new criticality modeling approaches have greatly increased the efficiency of dissolver operations in H-Canyon. The first new approach takes credit for the linear, physical distribution of the mass throughout the entire length of the fuel assembly. This distribution of mass is referred to as the linear density. Crediting the linear density of the fuel bundles results in using lower fissile concentrations, which allows higher masses to be charged to the dissolver. Also, this approach takes credit for the fact that only part of the fissile mass is wetted at a time. There are multiple assemblies stacked on top of each other in a bundle. On average, only 50-75% of the mass (the bottom two or three assemblies) is wetted at a time. This means that only 50-75% (depending on operating level) of the mass is moderated and is contributing to the reactivity of the system. The second new approach takes credit for the progression of the dissolving process. Previously, dissolving analysis looked at a snapshot in time where the same fissile material existed both in the wells and in the bulk solution at the same time. The second new approach models multiple consecutive phases that simulate the fissile material …
Date: August 15, 2011
Creator: Williamson, B.
System: The UNT Digital Library