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Three-dimensional lithographically-defined organotypic tissue arrays for quantitative analysis of morphogenesis and neoplastic progression

Description: Here we describe a simple micromolding method to construct three-dimensional arrays of organotypic epithelial tissue structures that approximate in vivo histology. An elastomeric stamp containing an array of posts of defined geometry and spacing is used to mold microscale cavities into the surface of type I collagen gels. Epithelial cells are seeded into the cavities and covered with a second layer of collagen. The cells reorganize into hollow tissues corresponding to the geometry of the caviti… more
Date: February 13, 2008
Creator: Nelson, Celeste M.; Inman, Jamie L. & Bissell, Mina J.
Partner: UNT Libraries Government Documents Department
open access

Multi-year search for a diffuse flxu of muon neutrinos with AMANDA-II

Description: A search for TeV-PeV muon neutrinos from unresolved sources was performed on AMANDA-II data collected between 2000 and 2003 with an equivalent livetime of 807 days. This diffuse analysis sought to find an extraterrestrial neutrino flux from sources with non-thermal components. The signal is expected to have a harder spectrum than the atmospheric muon and neutrino backgrounds. Since no excess of events was seen in the data over the expected background, an upper limit of E{sup 2}{Phi}{sub 90%C.L.… more
Date: April 13, 2008
Creator: Collaboration, IceCube; Klein, Spencer; Achterberg, A. & Collaboration, IceCube
Partner: UNT Libraries Government Documents Department
open access

Radiation monitoring with CVD Diamonds and PIN Diodes at BaBar

Description: The BaBar experiment at the Stanford Linear Accelerator Center has been using two polycrystalline chemical vapor deposition (pCVD) diamonds and 12 silicon PIN diodes for radiation monitoring and protection of the Silicon Vertex Tracker (SVT). We have used the pCVD diamonds for more than 3 years, and the PIN diodes for 7 years. We will describe the SVT and SVT radiation monitoring system as well as the operational difficulties and radiation damage effects on the PIN diodes and pCVD diamonds in a… more
Date: February 13, 2008
Creator: Bruinsma, M.; Burchat, P.; Curry, S.; Edwards, A.J.; Kagan, H.; Kass, R. et al.
Partner: UNT Libraries Government Documents Department
open access

Hyperfine Quenching of the 2s2p 3P0 State of Berylliumlike Ions

Description: The hyperfine-induced 2s2p {sup 3}P{sub 0}-2s{sup 2} {sup 1}S{sub 0} transition rate for Be-like {sup 47}Ti{sup 18+} was recently measured in a storage-ring experiment by Schippers et al. [Phys. Rev. Lett. 98, 033001 (2007)]. The measured value of 0.56(3) s{sup -1} is almost 60% larger than the theoretical value of 0.356 s{sup -1} from a multiconfiguration Dirac-Fock calculation by Marques et al. [Phys. Rev. A 47, 929 (1993)]. In this work, we use a large-scale relativistic configuration-intera… more
Date: March 13, 2008
Creator: Cheng, K T; Chen, M H & Johnson, W R
Partner: UNT Libraries Government Documents Department
open access

MARKOV Model Application to Proliferation Risk Reduction of an Advanced Nuclear System

Description: The Generation IV International Forum (GIF) emphasizes proliferation resistance and physical protection (PR&PP) as a main goal for future nuclear energy systems. The GIF PR&PP Working Group has developed a methodology for the evaluation of these systems. As an application of the methodology, Markov model has been developed for the evaluation of proliferation resistance and is demonstrated for a hypothetical Example Sodium Fast Reactor (ESFR) system. This paper presents the case of diver… more
Date: July 13, 2008
Creator: Bari, R. A.
Partner: UNT Libraries Government Documents Department
open access

Colloid Science of Metal Nanoparticle Catalysts in 2D and 3D Structures. Challenges of Nucleation, Growth, Composition, Particle Shape, Size Control and their Influence on Activity and Selectivity

Description: Recent breakthroughs in synthesis in nanosciences have achieved control of size and shapes of nanoparticles that are relevant for catalyst design. In this article, we review the advance of synthesis of nanoparticles, fabrication of two and three dimensional model catalyst system, characterization, and studies of activity and selectivity. The ability to synthesize monodispersed platinum and rhodium nanoparticles in the 1-10 nm range permitted us to study the influence of composition, structure, … more
Date: February 13, 2008
Creator: Somorjai, Gabor A. & Park, Jeong Y.
Partner: UNT Libraries Government Documents Department
open access

Charmless Two-Body and Quasi-Two-Body B-decays at BABAR

Description: The authors present improved measurements of the branching fractions and CP asymmetries in the two-body decays B{sup 0} {yields} {pi}{sup 0}{pi}{sup 0}, B{sup 0} {yields} K{sup 0}{pi}{sup 0} and B{sup 0} {yields} K{sup +}{pi}{sup -} as well as the quasi two-body B{sup 0} {yields} K{sub 1}(1270){sup +} {pi}{sup -} and B{sup 0} {yields} K{sub 1}(1400){sup +} {pi}{sup -} decays. These updated measurements are made using the complete set of BABAR data taken at the Y(4S) resonance, collected between… more
Date: October 13, 2008
Creator: Ofte, Ingrid
Partner: UNT Libraries Government Documents Department
open access

Shielding Calculations for NSLS-II Beamlines.

Description: Brookhaven National Laboratory is in the process of designing a new Electron Synchrotron for scientific research using synchrotron radiation. This facility, called the 'National Synchrotron Light Source II' (NSLS-II), will provide x-ray radiation of ultra-high brightness and exceptional spatial and energy resolution. It will also provide advanced insertion devices, optics, detectors, and robotics, and a suite of scientific instruments designed to maximize the scientific output of the facility. … more
Date: April 13, 2008
Creator: Job,P.K. & Casey, W.R.
Partner: UNT Libraries Government Documents Department
open access

Electronic Structure of Halogen Doped CuCr2Se4

Description: We have employed element and chemically sensitive X-ray absorption spectroscopy (XAS) and X-ray magnetic circular dichroism (XMCD) in order to address a long standing controversy regarding the electronic and magnetic state of CuCr{sub 2}Se{sub 4} via halogen doping of the Se anion site in CuCr{sub 2}Se{sub 4-x}Y{sub x} (Y=Cl and Br). Long range magnetic order is observed above room temperature for all samples. The Cr L{sub 2,3} XAS spectra show a prevalent 3+ valence for the Cr ions independent… more
Date: September 13, 2008
Creator: Arenholz, Elke; Liberati, M.; Neulinger, J. R.; Chopdekar, R. V.; Bettinger, J. S.; Arenholz, E. et al.
Partner: UNT Libraries Government Documents Department
open access

Machine-Detector Interface Issues for the ILCPolarimeters

Description: This note examines several Machine-Detector Interface (MDI) issues for the Compton polarimeters in the Beam Delivery System of the International Linear Collider (ILC), including (1) alignment tolerances, (2) impact of crossing angle and IR magnets on spin alignment, (3) Z-pole operation, and (4) costs and conventional facilities.
Date: June 13, 2008
Creator: Woods, Mike
Partner: UNT Libraries Government Documents Department
open access

CeBr3 as a High-Resolution Gamma-Ray Detector

Description: Lanthanum halide (LaBr3:Ce) scintillators have been well-documented as high-resolution gamma-ray detectors that are operated at room temperature. These scintillators have better resolution (<3% at 662 keV) relative to sodium iodide (NaI(Tl)) scintillators (7% at 662 keV), but the naturally occurring radioactive isotope 138La causes self-activity in the crystal that occludes portions of the gamma-ray spectrum. This selfactivity limits the use of LaBr3:Ce in high-sensitivity applications. Cerium,… more
Date: November 13, 2008
Creator: Michael Reed, Paul Guss, Christopher Contreras
Partner: UNT Libraries Government Documents Department
open access

Nanofiltration of Electrolyte Solutions by Sub-2nm Carbon Nanotube Membranes

Description: Both MD simulations and experimental studies have shown that liquid and gas flow through carbon nanotubes with nanometer size diameter is exceptionally fast. For applications in separation technology, selectivity is required together with fast flow. In this work, we use pressure-driven filtration experiments to study ion exclusion in silicon nitride/sub-2-nm CNT composite membranes as a function of solution ionic strength, pH, and ion valence. We show that carbon nanotube membranes exhibit sign… more
Date: March 13, 2008
Creator: Fornasiero, F.; Park, H. G.; Holt, J. K.; Stadermann, M.; Kim, S.; In, J. B. et al.
Partner: UNT Libraries Government Documents Department
open access

The US Support Program to IAEA Safeguards Priority of Containment and Surveillance

Description: The United States Support Program (USSP) priority for containment and surveillance (US) focuses on maintaining or improving the reliability and cost-effectiveness of C/S systems for IAEA safeguards, expanding the number of systems that are unattended and remotely monitored, and developing verification methods that help streamline the on-site inspection process. Existing IAEA C/S systems have evolved to become complex, integrated systems, which may include active seals, nondestructive assay (NDA… more
Date: June 13, 2008
Creator: Diaz,R.A.
Partner: UNT Libraries Government Documents Department
open access

Generation IV PR and PP Methods and Applications

Description: This paper presents an evaluation methodology for proliferation resistance and physical protection (PR&amp;PP) of Generation IV nuclear energy systems (NESs). For a proposed NES design, the methodology defines a set of challenges, analyzes system response to these challenges, and assesses outcomes. The challenges to the NES are the threats posed by potential actors (proliferant States or sub-national adversaries). The characteristics of Generation IV systems, both technical and institutional, a… more
Date: October 13, 2008
Creator: Bari, R. A.
Partner: UNT Libraries Government Documents Department
open access

Creep Testing Plastic-Bonded Explosives in Uni-axial Compression

Description: High fidelity measurements of time-dependent strain in the plastic-bonded explosives LX-17-1 and PBX 9502 have been performed under constant, uni-axial, compressive load using a custom designed apparatus. The apparatus uses a combination of extensometers and linear variable differential transformers coupled with a data acquisition system, thermal controls, and gravitational loading. The materials being tested consist of a crystalline explosive material mixed with a polymeric binder. The behavio… more
Date: March 13, 2008
Creator: Gagliardi, F J & Cunningham, B J
Partner: UNT Libraries Government Documents Department
open access

The U.S. Support Program to IAEA Safeguards - Destructive Analysis

Description: The U.S. Support Program (USSP) to IAEA Safeguards priority of destructive analysis is aimed at strengthening the IAEA's ability to use destructive analysis as a safeguards tool. IAEA inspectors bring back nuclear and environmental samples from inspections, which are first cataloged by the IAEA and then analyzed by a network of laboratories located in many Member States and the IAEA's own Safeguards Analytical Laboratory in Seibersdorf, Austria. Historically, the USSP was instrumental in introd… more
Date: July 13, 2008
Creator: Hoffheins,B.
Partner: UNT Libraries Government Documents Department
open access

A multi-model assessment of pollution transport to the Arctic

Description: We examine the response of Arctic gas and aerosol concentrations to perturbations in pollutant emissions from Europe, East and South Asia, and North America using results from a coordinated model intercomparison. These sensitivities to regional emissions (mixing ratio change per unit emission) vary widely across models and species. Intermodel differences are systematic, however, so that the relative importance of different regions is robust. North America contributes the most to Arctic ozone po… more
Date: March 13, 2008
Creator: Shindell, D T; Chin, M; Dentener, F; Doherty, R M; Faluvegi, G; Fiore, A M et al.
Partner: UNT Libraries Government Documents Department
open access

The AdS/CFT Correspondence and Light-Front QCD

Description: We identify an invariant light-front coordinate {zeta} which allows the separation of the dynamics of quark and gluon binding from the kinematics of constituent spin and internal orbital angular momentum. The result is a single-variable light-front Schroedinger equation for QCD which determines the eigenspectrum and the light-front wavefunctions of hadrons for general spin and orbital angular momentum. This frame-independent light-front wave equation is equivalent to the equations of motion whi… more
Date: October 13, 2008
Creator: Brodsky, Stanley J. & de Teramond, Guy F.
Partner: UNT Libraries Government Documents Department
open access

Product Quality Assurance for Off-Grid Lighting in Africa

Description: Although the emergence of markets for high efficiency off-grid lighting technologies holds promise, realizing the potential of this opportunity on a long-term, sustainable basis requires careful attention to issues of product quality, consumer protection, and the potential for significant 'market spoiling', in anticipation of increases of sales of low cost, low performance off-grid lighting products. The goal of the Lighting Africa quality assurance workshop was to articulate strategies to miti… more
Date: July 13, 2008
Creator: Bank, World; Mills, Evan & Mills, Evan
Partner: UNT Libraries Government Documents Department
open access

Alpha(phi2) From a Time-Dependent Analysis of B0 -> (rhopi)0 Dalitz-plot

Description: The authors present results of time-dependent Dalitz plot analyses of B{sup 0} {yields} ({rho}{pi}){sup 0} and the corresponding constraints on the angle {alpha} or {phi}{sub 2} of the CKM unitarity triangle from the B factories.
Date: October 13, 2008
Creator: Mohanty, G & U., Warwick
Partner: UNT Libraries Government Documents Department
open access

Mechanisms of disease: epithelial-mesenchymal transition and back again: does cellular plasticity fuel neoplastic progression?

Description: Epithelial-mesenchymal transition (EMT) is a conversion that facilitates organ morphogenesis and tissue remodeling in physiological processes such as embryonic development and wound healing. A similar phenotypic conversion is also detected in fibrotic diseases and neoplasia, which is associated with disease progression. EMT in cancer epithelial cells often seems to be an incomplete and bi-directional process. In this Review, we discuss the phenomenon of EMT as it pertains to tumor development, … more
Date: February 13, 2008
Creator: Bissell, Mina J; Turley, Eva A.; Veiseh, Mandana; Radisky, Derek C. & Bissell, Mina J.
Partner: UNT Libraries Government Documents Department
open access

Mechanical Design of the LSST Camera

Description: The LSST camera is a tightly packaged, hermetically-sealed system that is cantilevered into the main beam of the LSST telescope. It is comprised of three refractive lenses, on-board storage for five large filters, a high-precision shutter, and a cryostat that houses the 3.2 giga-pixel CCD focal plane along with its support electronics. The physically large optics and focal plane demand large structural elements to support them, but the overall size of the camera and its components must be minim… more
Date: June 13, 2008
Creator: Nordby, Martin; Bowden, Gordon; Foss, Mike; Guiffre, Gary; Ku, John & Schindler, Rafe
Partner: UNT Libraries Government Documents Department
open access

Prompt gamma activation analysis (PGAA) and short-lived neutron activation analysis (NAA) applied to the characterization of legacy materials

Description: Without quality historical records that provide the composition of legacy materials, the elemental and/or chemical characterization of such materials requires a manual analytical strategy that may expose the analyst to unknown toxicological hazards. In addition, much of the existing legacy inventory also incorporates radioactivity, and, although radiological composition may be determined by various nuclear-analytical methods, most importantly, gamma-spectroscopy, current methods of chemical cha… more
Date: February 13, 2008
Creator: Firestone, Richard B; English, G. A.; Firestone, R. B.; Perry, D. L.; Reijonen, J. P.; Leung, Ka-Ngo et al.
Partner: UNT Libraries Government Documents Department
open access

DHS Regional Reachback: Rapid Expert Radiation Alarm Assistance.

Description: Following assessments that attacks with radiological and nuclear weapons are possible, detection system deployments are being supported at national and local levels. Detection systems include both, highly sensitive but non-discriminating detectors, as well as detectors and algorithms capable of distinguishing and identifying gamma rays by energy. The latter systems, usually handheld systems based on sodium iodide detectors, also provide analysis of the specific radionuclides present and are ref… more
Date: July 13, 2008
Creator: Bowerman, B.; Archer, D.; Young, J.; Monetti, M. & Savage, B.
Partner: UNT Libraries Government Documents Department
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