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SATB1 tethers multiple gene loci to reprogram expression profiledriving breast cancer metastasis

Description: Global changes in gene expression occur during tumor progression, as indicated by expression profiling of metastatic tumors. How this occurs is poorly understood. SATB1 functions as a genome organizer by folding chromatin via tethering multiple genomic loci and recruiting chromatin remodeling enzymes to regulate chromatin structure and expression of a large number of genes. Here we show that SATB1 is expressed at high levels in aggressive breast cancer cells, and is undetectable in non-malignan… more
Date: July 13, 2006
Creator: Han, Hye-Jung; Kohwi, Yoshinori & Kohwi-Shigematsu, Terumi
Partner: UNT Libraries Government Documents Department
open access

Transmission Electron Microscopy Study of InN Nanorods

Description: InN nanorods were grown on a, c-, and r-plane of sapphire and also on Si (111) and GaN (0001) by non-catalytic, template-free hydride metal-organic vapor phase epitaxy and studied by transmission electron microscopy, electron energy loss (EELS) and photoluminescence (PL) at room temperature. These nanocrystals have different shapes and different faceting depending on the substrate used and their crystallographic orientation. EELS measurements have confirmed the high purity of these crystals. Th… more
Date: July 13, 2006
Creator: Liliental-Weber, Z.; Li, X.; Kryliouk, Olga; Park, H.J.; Mangum,J. & Anderson, T.
Partner: UNT Libraries Government Documents Department
open access

Incorporation of aqueous reaction kinetics and biodegradation intoTOUGHREACT: Application of a multi-region model to hydrobiogeoChemicaltransport of denitrification and sulfate reduction

Description: The need to consider aqueous and sorption kinetics andmicrobiological processes arises in many subsurface problems. Ageneral-rate expression has been implemented into the TOUGHREACTsimulator, which considers multiple mechanisms (pathways) and includesmultiple product, Monod, and inhibition terms. This paper presents aformulation for incorporating kinetic rates among primary species intomass-balance equations. The space discretization used is based on aflexible integral finite difference approac… more
Date: July 13, 2006
Creator: Xu, Tianfu
Partner: UNT Libraries Government Documents Department
open access

Germanium-Based Detectors for Gamma-Ray Imaging andSpectroscopy

Description: Germanium-based detectors are the standard technology usedfor gamma-ray spectroscopy when high efficiency and excellent energyresolution are desired. By dividing the electrical contacts on thesedetectors into segments, the locations of the gamma-ray interactionevents within the detectors can be determined as well as the depositedenergies. This enables simultaneous gamma-ray imaging and spectroscopyand leads to applications in the areas of astronomy, nuclear physics,environmental remediation, nu… more
Date: October 13, 2006
Creator: Amman, Mark; Luke, Paul N. & Boggs, Steven E.
Partner: UNT Libraries Government Documents Department
open access

Time-Resolved FT-IR Spectroscopy of CO Hydrogenation overSupported Ru Catalyst at 700K

Description: Time-resolved FT-IR spectra of carbon monoxide hydrogenation over alumina-supported ruthenium were recorded on the millisecond timescale at 703 K using various H{sub 2} concentrations (1 atm total pressure). Adsorbed carbon monoxide was detected along with gas phase products methane (3016 and 1306 cm{sup -1}), water (sharp bands from 1900 - 1300 cm{sup -1}), and carbon dioxide (2348 cm{sup -1}). No other surface species were detected other than adsorbed carbon monoxide. The rate of formation of… more
Date: February 13, 2006
Creator: Wasylenko, Walter & Frei, Heinz
Partner: UNT Libraries Government Documents Department
open access

Theory and Simulation of Warm Dense Matter Targets

Description: We present simulations and analysis of the heating of warm dense matter foils by ion beams with ion energy less than one MeV per nucleon to target temperatures of order one eV. Simulations were carried out using the multi-physics radiation hydrodynamics code HYDRA and comparisons are made with analysis and the code DPC. We simulate possible targets for a proposed experiment at LBNL (the so-called Neutralized Drift Compression Experiment, NDCXII) for studies of warm dense matter. We compare the … more
Date: July 13, 2006
Creator: Barnard, J. J.; Armijo, J.; More, R. M.; Friedman, A.; Kaganovich, I.; Logan, B. G. et al.
Partner: UNT Libraries Government Documents Department
open access

Computing Criticality of Lines in Power Systems

Description: 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 … more
Date: October 13, 2006
Creator: Pinar, Ali; Reichert, Adam & Lesieutre, Bernard
Partner: UNT Libraries Government Documents Department
open access

Integrated Global Nuclear Materials Management - Preliminary Concepts -

Description: Approach to Connect Global Objectives and Local Actions: (1) Articulate global objectives into a hierarchy of subsystem requirements and local attributes and measures; (2) Establish a baseline system and viable alternatives through the interactions and relationships (e.g., networks) of local system elements and their options; (3) Evaluate performance of system alternatives and develop improved nuclear material management strategies and technologies; and (4) The need to address greatest concerns… more
Date: July 13, 2006
Creator: Dreicer, M; Jones, E & Richardson, J
Partner: UNT Libraries Government Documents Department
open access

Sequencing and Analysis of Neanderthal Genomic DNA

Description: Recovery and analysis of multiple Neanderthal autosomalsequences using a metagenomic approach reveals that modern humans andNeanderthals split ~;400,000 years ago, without significant evidence ofsubsequent admixture.
Date: June 13, 2006
Creator: Noonan, James P.; Coop, Graham; Kudaravalli, Sridhar; Smith,Doug; Krause, Johannes; Alessi, Joe et al.
Partner: UNT Libraries Government Documents Department
open access

Radiocarbon Based Ages and Growth Rates: Hawaiian Deep Sea Corals

Description: The radial growth rates and ages of three different groups of Hawaiian deep-sea 'corals' were determined using radiocarbon measurements. Specimens of Corallium secundum, Gerardia sp., and Leiopathes glaberrima, were collected from 450 {+-} 40 m at the Makapuu deep-sea coral bed using a submersible (PISCES V). Specimens of Antipathes dichotoma were collected at 50 m off Lahaina, Maui. The primary source of carbon to the calcitic C. secundum skeleton is in situ dissolved inorganic carbon (DIC). U… more
Date: January 13, 2006
Creator: Roark, E. B.; Guilderson, T. P.; Dunbar, R. B. & Ingram, B. L.
Partner: UNT Libraries Government Documents Department
open access

Physics of reshock and mixing in single-mode Richtmyer-Meshkov instability

Description: The ninth-order weighted essentially non-oscillatory (WENO) shock-capturing method is used to investigate the physics of reshock and mixing in two-dimensional single-mode Richtmyer-Meshkov instability to late times. The initial conditions and computational domain were adapted from the Mach 1.21 air(acetone)/SF{sub 6} shock tube experiment of Collins and Jacobs [J. Fluid Mech. 464, 113 (2002)]: the growth of the bubble and spike perturbation amplitudes from fifth- and ninth-order WENO simulation… more
Date: December 13, 2006
Creator: Schilling, O; Latini, M & Don, W
Partner: UNT Libraries Government Documents Department
open access

Comment on "Paleoclassical Transport in Low-Collisionality Toroidal Plasmas"

Description: Paleoclassical transport [1] is a recently proposed fundamental process that is claimed to occur in resistive plasmas and to be missing in the collisional drift-kinetic equations (DKE) in standard use. In this Comment we raise three puzzles presented by paleoclassical transport as developed in [1], one to do with conservation and two concerning uniqueness.
Date: October 13, 2006
Creator: LoDestro, L. L.
Partner: UNT Libraries Government Documents Department
open access

A Strong-Lens Survey in AEGIS: the influence of large scalestructure

Description: We report on the results of a visual search for galaxy-scale strong gravitational lenses over 650 arcmin{sup 2} of HST/ACS (F606W and F814W) imaging in the DEEP2-Extended Groth Strip (EGS). In addition to a previously-known Einstein Cross also found by our search (the 'Cross', HSTJ141735+52264, z{sub lens} = 0.8106, z{sub source} = 3.40), we identify two new strong galaxy-galaxy lenses with multiple extended arcs. The first, HSTJ141820+52361 (the 'Dewdrop'; z{sub lens} = 0.5798), lenses two dis… more
Date: October 13, 2006
Creator: Moustakas, Leonidas A.; Marshall, Phil; Newman, Jeffrey A.; Coil,Alison L.; Cooper, Michael C.; Davis, Marc et al.
Partner: UNT Libraries Government Documents Department
open access

A High-Resolution Godunov Method for Compressible Multi-Material Flow on Overlapping Grids

Description: A numerical method is described for inviscid, compressible, multi-material flow in two space dimensions. The flow is governed by the multi-material Euler equations with a general mixture equation of state. Composite overlapping grids are used to handle complex flow geometry and block-structured adaptive mesh refinement (AMR) is used to locally increase grid resolution near shocks and material interfaces. The discretization of the governing equations is based on a high-resolution Godunov method,… more
Date: February 13, 2006
Creator: Banks, J W; Schwendeman, D W; Kapila, A K & Henshaw, W D
Partner: UNT Libraries Government Documents Department
open access

Calculation of Photoneutrons from Varian Clinac Accelerators and Their Transmissions in Materials

Description: Monte Carlo calculations of the giant-dipole-resonance photoneutrons (GRN) around the Varian Clinac 2100C/2300C medical accelerator heads (10-20 MV modes) were made using the coupled EGS4-MORSE code. The actual head materials and geometries were simulated in great detail using the Combinatorial Geometry facility of MORSE. The neutron production (i.e., sites and yields) was calculated with EGS4 and, then, the neutron transport in the accelerator head was done with MORSE. Both the evaporation and… more
Date: November 13, 2006
Creator: Liu, J. C.; Kase, K. R.; Mao, X. S.; Nelson, W. R.; Kleck, J. H. & Johnson, S.
Partner: UNT Libraries Government Documents Department
open access

Calculation of Neutral Beam Injection into SSPX

Description: The SSPX spheromak experiment has achieved electron temperatures of 350eV and confinement consistent with closed magnetic surfaces. In addition, there is evidence that the experiment may be up against an operational beta limit for Ohmic heating. To test this barrier, there are firm plans to add two 0.9MW Neutral Beam (NB) sources to the experiment. A question is whether the limit is due to instability. Since the deposited Ohmic power in the core is relatively small the additional power from the… more
Date: June 13, 2006
Creator: Pearlstein, L. D.; Casper, T. A.; Hill, D. N.; LoDestro, L. L. & McLean, H. S.
Partner: UNT Libraries Government Documents Department
open access

Adsorption Mechanisms of Trivalent Gold onto Iron Oxy-Hydroxides: From the Molecular Scale to the Model

Description: Gold is a highly valuable metal that can concentrate in iron-rich exogenetic horizons such as laterites. An improved knowledge of the retention mechanisms of gold onto highly reactive soil components such as iron oxyhydroxides is therefore needed to better understand and predict the geochemical behavior of this element. In this study, we use EXAFS information and titration experiments to provide a realistic thermochemical description of the sorption of trivalent gold onto iron oxy-hydroxides. A… more
Date: December 13, 2006
Creator: Cances, Benjamin; Benedetti, Marc; Farges, Francois; Brown, Gordon E., Jr. & /Stanford U., Geo. Environ. Sci. /SLAC, SSRL
Partner: UNT Libraries Government Documents Department
open access

On the Coordination of Actinides and Fission Products in Silicate Glasses

Description: The local structure around Th, U, Ce and Nd in leached silicate glasses was examined using XAFS spectroscopy at their L3 edges and also at the K edge of Fe, Co, Ni, Zr and Mo. Pellets of inactive borosilicate glasses with a simplified or a complex composition were leached statically at 90 C, at pH buffered to 0 or 6 for 28 days (surface/volume, S/V, ratios of 0.1 cm{sup -1}). These glasses are compared to another SON68 sample (denoted ''SP1'' in this paper) that was statically leached for 12 ye… more
Date: December 13, 2006
Creator: Haddi, Anne; U., /Marne la Vallee; Farges, Francois; /Marne la Vallee U. /Museum Nat. Hist., Paris /Stanford U., Geo. Environ. Sci.; Trocellier, Patrick; /Saclay et al.
Partner: UNT Libraries Government Documents Department
open access

Lanczos and Recursion Techniques for Multiscale Kinetic Monte Carlo Simulations

Description: We review an approach to the simulation of the class of microstructural and morphological evolution involving both relatively short-ranged chemical and interfacial interactions and long-ranged elastic interactions. The calculation of the anharmonic elastic energy is facilitated with Lanczos recursion. The elastic energy changes affect the rate of vacancy hopping, and hence the rate of microstructural evolution due to vacancy mediated diffusion. The elastically informed hopping rates are used to… more
Date: March 13, 2006
Creator: Rudd, R E; Mason, D R & Sutton, A P
Partner: UNT Libraries Government Documents Department
open access

Support for Whole-Program Analysis and the Verification of the One-Definition Rule in C++

Description: We present a compact and accurate representation of a whole-program abstract syntax tree, and use it to detect a specific security vulnerability in C++ programs known as a One-Definition Rule (ODR) violation. The ODR states that types and functions appearing in multiple compilation units must be defined identically. However, no current compiler can enforce ODR because doing so requires the ability to see the full application source at once; where ODR is violated, the program is incorrect. Moreo… more
Date: June 13, 2006
Creator: Quinlan, D; Vuduc, R; Panas, T; Haerdtlein, J & Saebjoernsen, A
Partner: UNT Libraries Government Documents Department
open access

Femtosecond Diffractive Imaging with a Soft-X-ray Free-Electron Laser

Description: Theory predicts that with an ultrashort and extremely bright coherent X-ray pulse, a single diffraction pattern may be recorded from a large macromolecule, a virus, or a cell before the sample explodes and turns into a plasma. Here we report the first experimental demonstration of this principle using the FLASH soft X-ray free-electron laser. An intense 25 fs, 4 x 10{sup 13} W/cm{sup 2} pulse, containing 10{sup 12} photons at 32 nm wavelength, produced a coherent diffraction pattern from a nano… more
Date: March 13, 2006
Creator: Chapman, H. N.; Barty, A.; Bogan, M.; Boutet, S.; Frank, M.; Hau-Riege, S. P. et al.
Partner: UNT Libraries Government Documents Department
open access

Dual-phase argon ionization detector for measurement of coherent elastic neutrino scattering and medium-energy nuclear recoils

Description: We propose to build and deploy a 10-kg dual-phase argon ionization detector for the detection of coherent neutrino-nucleus scattering, which is described by the reaction; (V) + (Z,N) {yields} (v) + (Z,N). Our group would be the first to make this measurement. Its detection would validate (or refute) central tenets of the Standard Model. The existence of this process is also relevant to astrophysics, where coherent neutrino scattering is assumed to impede energy transport within neutron stars. W… more
Date: September 13, 2006
Creator: Winant, C D; Bernstein, A; Hagmann, C; Madden, N & Stoeffl, W
Partner: UNT Libraries Government Documents Department
open access

Efficient Schemes for Reducing Numerical Dispersion in ModelingMultiphase Transport through Porous and Fractured Media

Description: Numerical issues with modeling transport of chemicals or solute in realistic large-scale subsurface systems have been a serious concern, even with the continual progress made in both simulation algorithms and computer hardware in the past few decades. The problem remains and becomes even more difficult when dealing with chemical transport in a multiphase flow system using coarse, multidimensional regular or irregular grids, because of the known effects of numerical dispersion associated with mo… more
Date: April 13, 2006
Creator: Wu, Yu-Shu & Forsyth, Peter A.
Partner: UNT Libraries Government Documents Department
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