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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

Unexpected Cancellations in Gravity Theories

Description: Recent computations of scattering amplitudes show that N = 8 supergravity is surprisingly well behaved in the ultraviolet and may even be ultraviolet finite in perturbation theory. The novel cancellations necessary for ultraviolet finiteness first appear at one loop in the guise of the ''no-triangle hypothesis''. We study one-loop amplitudes in pure Einstein gravity and point out the existence of cancellations similar to those found previously in N = 8 supergravity. These cancellations go beyon… more
Date: July 13, 2007
Creator: Bern, Z.; Carrasco, J.J.; /UCLA; Forde, D.; /SLAC, /UCLA; Ita, H. et al.
Partner: UNT Libraries Government Documents Department
open access

Event-by-Event Simulation of Induced Fission

Description: We are developing a novel code that treats induced fission by statistical (or Monte-Carlo) simulation of individual decay chains. After its initial excitation, the fissionable compound nucleus may either deexcite by evaporation or undergo binary fission into a large number of fission channels each with different energetics involving both energy dissipation and deformed scission prefragments. After separation and Coulomb acceleration, each fission fragment undergoes a succession of individual (n… more
Date: December 13, 2007
Creator: Vogt, R. & Randrup, J.
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

MONITORING WASTE HEAT REJECTION TO THE ENVIRONMENT VIA REMOTE SENSING

Description: Nuclear power plants typically use waste heat rejection systems such as cooling lakes and natural draft cooling towers. These systems are designed to reduce cooling water temperatures sufficiently to allow full power operation even during adverse meteorological conditions. After the power plant is operational, the performance of the cooling system is assessed. These assessments usually rely on measured temperatures of the cooling water after it has lost heat to the environment and is being pump… more
Date: January 13, 2009
Creator: Garrett, A
Partner: UNT Libraries Government Documents Department
open access

Flux analysis of central metabolic pathways in the Fe(III)-reducing organism Geobacter metallireducens via 13C isotopiclabeling

Description: We analyzed the carbon fluxes in the central metabolism ofGeobacter metallireducens strain GS-15 using 13C isotopomer modeling.Acetate labeled in the 1st or 2nd position was the sole carbon source,and Fe-NTA was the sole terminal electron acceptor. The measured labeledacetate uptake rate was 21 mmol/gdw/h in the exponential growth phase.The resulting isotope labeling pattern of amino acids allowed an accuratedetermination of the in vivo global metabolic reaction rates (fluxes)through the centra… more
Date: August 13, 2007
Creator: Tang, Yinjie J.; Chakraborty, Romy; Martin, Hector Garcia; Chu,Jeannie; Hazen, Terry C. & Keasling, Jay D.
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

Morphological tranformation of calcite crystal growth by prismatic "acidic" polypeptide sequences.

Description: Many of the interesting mechanical and materials properties of the mollusk shell are thought to stem from the prismatic calcite crystal assemblies within this composite structure. It is now evident that proteins play a major role in the formation of these assemblies. Recently, a superfamily of 7 conserved prismatic layer-specific mollusk shell proteins, Asprich, were sequenced, and the 42 AA C-terminal sequence region of this protein superfamily was found to introduce surface voids or porositie… more
Date: February 13, 2007
Creator: Kim, I; Giocondi, J L; Orme, C A; Collino, J & Evans, J S
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

Evidence for Groundwater Contamination Vulnerability in California?s Central Valley

Description: The California Water Resources Control Board, in collaboration with the US Geological Survey and Lawrence Livermore National Laboratory, has implemented a program to assess the susceptibility of groundwater resources. Advanced techniques such as groundwater age dating using the tritium-helium method, extensive use of oxygen isotopes of the water molecule ({delta}{sup 18}O) for recharge water provenance, and analysis of common volatile organic compounds (VOCs) at ultra-low levels are applied wit… more
Date: December 13, 2005
Creator: Moran, J. E.; Leif, R.; Esser, B. K. & Singleton, M. J.
Partner: UNT Libraries Government Documents Department
open access

A brief review of the intensity of lines 3C and 3D in neon-like Fe XVII

Description: X-ray emission from neon-like Fe XVII has been measured with high-resolution spectrometers from laboratory or celestial sources for nearly seven decades. Two of the strongest lines regularly identified in these spectra are the {sup 1}P{sub 1} {yields} {sup 1}S{sub 0} resonance, and {sup 3}D{sub 1} {yields} {sup 1}S{sub 0} intercombination line, known as 3C and 3D, respectively. This paper gives a brief overview of measurements of the intensities of the lines 3C and 3D from laboratory and celest… more
Date: June 13, 2007
Creator: Brown, G V
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

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

Toward a simple molecular understanding of sum frequency generation at air-water interfaces

Description: Second-order vibrational spectroscopies successfully isolate signals from interfaces, but they report on intermolecular structure in a complicated and indirect way. Here we adapt a perspective on vibrational response developed for bulk spectroscopies to explore the microscopic fluctuations to which sum frequency generation (SFG), a popular surface-specific measurement, is most sensitive. We focus exclusively on inhomogeneous broadening of spectral susceptibilities for OH stretching of HOD as a … more
Date: January 13, 2009
Creator: Noah-Vanhoucke, Joyce; Smith, Jared D. & Geissler, Phillip L.
Partner: UNT Libraries Government Documents Department
open access

Two Strategies to Speed up Connected Component LabelingAlgorithms

Description: This paper presents two new strategies to speed up connectedcomponent labeling algorithms. The first strategy employs a decisiontreeto minimize the work performed in the scanning phase of connectedcomponent labeling algorithms. The second strategy uses a simplifiedunion-find data structure to represent the equivalence information amongthe labels. For 8-connected components in atwo-dimensional (2D) image,the first strategy reduces the number of neighboring pixels visited from4 to7/3 on average. … more
Date: November 13, 2005
Creator: Wu, Kesheng; Otoo, Ekow & Suzuki, Kenji
Partner: UNT Libraries Government Documents Department
open access

Regulation of In Situ to Invasive Breast Carcinoma Transition

Description: The transition of ductal carcinoma in situ (DCIS) to invasive carcinoma is a key event in breast tumor progression that is poorly understood. Comparative molecular analysis of tumor epithelial cells from in situ and invasive tumors has failed to identify consistent tumor stage-specific differences. However, the myoepithelial cell layer, present only in DCIS, is a key distinguishing and diagnostic feature. To determine the contribution of non-epithelial cells to tumor progression, we analyzed th… more
Date: March 13, 2007
Creator: Hu, Min; Carroll, Danielle K.; Weremowicz, Stanislawa; Chen, Haiyan; Carrasco, Daniel; Richardson, Andrea et al.
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

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

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
open access

Closed-String Tachyon Condensation and the Worldsheet Super-Higgs Effect

Description: Alternative gauge choices for worldsheet supersymmetry can elucidate dynamical phenomena obscured in the usual superconformal gauge. In the particular example of the tachyonic E_8 heterotic string, we use a judicious gauge choice to show that the process of closed-string tachyon condensation can be understood in terms of a worldsheet super-Higgs effect. The worldsheet gravitino assimilates the goldstino and becomes a dynamical propagating field. Conformal, but not superconformal, invariance is … more
Date: September 13, 2007
Creator: Horava, Petr; Horava, Petr & Keeler, Cynthia A.
Partner: UNT Libraries Government Documents Department
open access

Chandra Reveals Twin X-ray Jets in the Powerful FR-II Radio Galaxy 3C353

Description: We report X-ray imaging of the powerful FR II radio galaxy 3C 353 using the Chandra X-ray Observatory. 3C 353's two 4-inch wide and 2-feet long jets allow us to study in detail the internal structure of the large-scale relativistic outflows at both radio and X-ray photon energies with the sub-arcsecond spatial resolution provided by the VLA and Chandra instruments. In a 90 ks Chandra observation, we have detected X-ray emission from most radio structures in 3C 353, including the nucleus, the je… more
Date: June 13, 2008
Creator: Kataoka, J.; Stawarz, L.; Harris, D.E.; Siemiginowska, A.; Ostrowski, M.; Swain, M.R. et al.
Partner: UNT Libraries Government Documents Department
open access

Recent Developments in Impact and Application to Future Light Sources

Description: This paper discusses two recently added capabilities of the IMPACT suite that are relevant to modeling electron linacs, namely the new 1D coherent synchrotron radiation (CSR) modeling capability and the integrated Green's function (IFG) algorithm for modeling high aspect ratio beams. In addition, we present initial results of application of the enhanced version of IMPACT-Z to high-fidelity modeling of the microbunching instability in a realistic light source lattice.
Date: February 13, 2008
Creator: Pogorelov, I.; Qiang, J.; Ryne, R.; Venturini, M.; Zholents, A. & Warnock, R.
Partner: UNT Libraries Government Documents Department
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