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2012 BIOINSPIRED MATERIALS GORDON RESEARCH CONFERENCE, JUNE 24-29, 2012 (open access)

2012 BIOINSPIRED MATERIALS GORDON RESEARCH CONFERENCE, JUNE 24-29, 2012

The emerging, interdisciplinary field of Bioinspired Materials focuses on developing a fundamental understanding of the synthesis, directed self-assembly and hierarchical organization of natural occurring materials, and uses this understanding to engineer new bioinspired artificial materials for diverse applications. The inaugural 2012 Gordon Conference on Bioinspired Materials seeks to capture the excitement of this burgeoning field by a cutting-edge scientific program and roster of distinguished invited speakers and discussion leaders who will address the key issues in the field. The Conference will feature a wide range of topics, such as materials and devices from DNA, reprogramming the genetic code for design of new materials, peptide, protein and carbohydrate based materials, biomimetic systems, complexity in self-assembly, and biomedical applications of bioinspired materials.
Date: June 29, 2013
Creator: Chilkoti, Ashutosh
System: The UNT Digital Library
2012 CORRELATED ELECTRON SYSTEMS GRC AND GRS, JUNE 23-29, 2012 (open access)

2012 CORRELATED ELECTRON SYSTEMS GRC AND GRS, JUNE 23-29, 2012

The 2012 Gordon Conference on Correlated Electron Systems will present cutting-edge research on emergent properties arising from strong electronic correlations. While we expect the discussion at the meeting to be wide-ranging, given the breadth of the title subject matter, we have chosen several topics to be the particular focus of the talks. These are New Developments in Single and Bilayer Graphene, Topological States of Matter, including Topological Insulators and Spin Liquids, the Interplay Between Magnetism and Unconventional Superconductivity, and Quantum Critical Phenomena in Metallic Systems. We also plan to have shorter sessions on Systems Far From Equilibrium, Low Dimensional Electron Fluids, and New Directions (which will primarily focus on new experimental methodologies and their interpretation).
Date: June 29, 2012
Creator: Kivelson, Steven
System: The UNT Digital Library
An advanced object-based software framework for complex ecosystem modeling and simulation (open access)

An advanced object-based software framework for complex ecosystem modeling and simulation

Military land managers and decision makers face an ever increasing challenge to balance maximum flexibility for the mission with a diverse set of multiple land use, social, political, and economic goals. In addition, these goals encompass environmental requirements for maintaining ecosystem health and sustainability over the long term. Spatiotemporal modeling and simulation in support of adaptive ecosystem management can be best accomplished through a dynamic, integrated, and flexible approach that incorporates scientific and technological components into a comprehensive ecosystem modeling framework. The Integrated Dynamic Landscape Analysis and Modeling System (IDLAMS) integrates ecological models and decision support techniques through a geographic information system (GIS)-based backbone. Recently, an object-oriented (OO) architectural framework was developed for IDLAMS (OO-IDLAMS). This OO-IDLAMS Prototype was built upon and leverages from the Dynamic Information Architecture System (DIAS) developed by Argonne National Laboratory. DIAS is an object-based architectural framework that affords a more integrated, dynamic, and flexible approach to comprehensive ecosystem modeling than was possible with the GIS-based integration approach of the original IDLAMS. The flexibility, dynamics, and interoperability demonstrated through this case study of an object-oriented approach have the potential to provide key technology solutions for many of the military's multiple-use goals and needs for integrated natural …
Date: June 29, 2000
Creator: Sydelko, P. J.; Dolph, J. E.; Majerus, K. A. & Taxon, T. N.
System: The UNT Digital Library
Algebraic Multigrid for Linear Systems Obtained by Explicit Element Reduction (open access)

Algebraic Multigrid for Linear Systems Obtained by Explicit Element Reduction

None
Date: June 29, 2010
Creator: Brunner, T. A. & Kolev, T. V.
System: The UNT Digital Library
Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression (open access)

Alpha1 and Alpha2 Integrins Mediate Invasive Activity of Mouse Mammary Carcinoma Cells through Regulation of Stromelysin-1 Expression

Tumor cell invasion relies on cell migration and extracellular matrix proteolysis. We investigated the contribution of different integrins to the invasive activity of mouse mammary carcinoma cells. Antibodies against integrin subunits {alpha}6 and {beta}1, but not against {alpha}1 and {alpha}2, inhibited cell locomotion on a reconstituted basement membrane in two-dimensional cell migration assays, whereas antibodies against {beta}1, but not against a6 or {alpha}2, interfered with cell adhesion to basement membrane constituents. Blocking antibodies against {alpha}1 integrins impaired only cell adhesion to type IV collagen. Antibodies against {alpha}1, {alpha}2, {alpha}6, and {beta}1, but not {alpha}5, integrin subunits reduced invasion of a reconstituted basement membrane. Integrins {alpha}1 and {alpha}2, which contributed only marginally to motility and adhesion, regulated proteinase production. Antibodies against {alpha}1 and {alpha}2, but not {alpha}6 and {beta}1, integrin subunits inhibited both transcription and protein expression of the matrix metalloproteinase stromelysin-1. Inhibition of tumor cell invasion by antibodies against {alpha}1 and {alpha}2 was reversed by addition of recombinant stromelysin-1. In contrast, stromelysin-1 could not rescue invasion inhibited by anti-{alpha}6 antibodies. Our data indicate that {alpha}1 and {alpha}2 integrins confer invasive behavior by regulating stromelysin-1 expression, whereas {alpha}6 integrins regulate cell motility. These results provide new insights into the specific functions …
Date: June 29, 1998
Creator: Lochter, Andre; Navre, Marc; Werb, Zena & Bissell, Mina J
System: The UNT Digital Library
The Anatomy of a Quadruply Imaged Gravitational Lens System (open access)

The Anatomy of a Quadruply Imaged Gravitational Lens System

The key to using a strong gravitational lens system to measure the Hubble constant is to obtain an accurate model of the lens potential. In this paper, we investigate the properties of gravitational lens B1608+656, a quadruply-imaged lens system with an extended source intensity distribution. Our analysis is valid for generic quadruply-lensed systems. Limit curves and isophotal separatrices are defined for such systems, and we show that the isophotal separatrices must intersect at the critical curves and the satellite isophotes must be tangent to the limit curves. The current model of B1608+656 (Koopmans et al. 2003) satisfies these criteria for some, but not all, of the isophotal separatrices within the observational uncertainty.We study a non-parametric method of potential reconstruction proposed by Blandford, Surpi & Kundic (2001) and demonstrate that although the method works in principle and elucidates image formation, the initial potential only converges to the true model when it is within {approx} 1 percent of the true model.
Date: June 29, 2005
Creator: Suyu, Sherry H. & Blandford, R. D.
System: The UNT Digital Library
Application of solution techniques to rapid growth of organic crystals (open access)

Application of solution techniques to rapid growth of organic crystals

None
Date: June 29, 2010
Creator: Zaitseva, N.; Carman, L.; Glenn, A.; Newby, J.; Faust, M.; Hamel, S. et al.
System: The UNT Digital Library
Atmospheric transport analysis used in hazard screening methodology (open access)

Atmospheric transport analysis used in hazard screening methodology

Simple, but conservative, atmospheric transport models are used in the initial stages of a hazard screening methodology to determine a preliminary hazard rank. The hazard rank is one indicator of the additional effort, if any, that must be applied to determine if a system is safe. Simple methods avoid prolonged calculations at this early stage when details of potential accidents may be poorly defined. The models are used to simulate the consequences resulting from accidental releases of toxic substances. Instantaneous and constant-rate releases are considered. If a release takes place within a relatively small enclosure, the close-in transport is approximated by assuming the airborne material is instantaneously mixed with the volume of air within this enclosure. For all other situations and large distances, the transport is estimated with simple atmospheric dispersion models using published values of dispersion coefficients for large distances, and values based on turbulent diffusion theory for close-in distances. Consequences are assessed by defining exposure levels that are equivalent to negligible, reversible, and irreversible health effects. The hazard rank is related to the number and location of people within each category of health effects.
Date: June 29, 1992
Creator: Bloom, S. G.
System: The UNT Digital Library
Baryon number and strangeness: signals of a deconfinedantecedent (open access)

Baryon number and strangeness: signals of a deconfinedantecedent

The correlation between baryon number and strangeness is used to discern the nature of the deconfined matter produced at vanishing chemical potential in high-energy nuclear collisions at the BNL RHIC. Comparisons of results of various phenomenological models with correlations extracted from lattice QCD calculations suggest that a quasi-particle picture applies. At finite baryon densities, such as those encountered at the CERN SPS, it is demonstrated that the presence of a first-order phase transition and the accompanying development of spinodal decomposition would significantly enhance the number of strangeness carriers and the associated fluctuations.
Date: June 29, 2005
Creator: Majumder, A.; Koch, V. & Randrup, J.
System: The UNT Digital Library
Bioinspired Synthesis of Silver Nanoparticles for the Remediation of Toxic Pollutants and Enhanced Antibacterial Activity (open access)

Bioinspired Synthesis of Silver Nanoparticles for the Remediation of Toxic Pollutants and Enhanced Antibacterial Activity

Article asserts that this research presents a novel and environmentally friendly approach for the synthesis of multifunctional nanobiocomposites for the efficient removal of toxic heavy metal and dye, as well as the disinfection of wastewater microorganisms. The synthesized bioinspired nanocomposite KAC-CS-AgNPs could be an innovative solution for effective and sustainable wastewater treatment and has great potential for commercial applications.
Date: June 29, 2023
Creator: Mandal, Sujata; Hwang, Sangchul; Marpu, Sreekar B.; Omary, Mohammad A.; Prybutok, Victor R. & Shi, Sheldon
System: The UNT Digital Library
Branching Fraction for B+ -> pi0 l+ nu, Measured in Upsilon (4S) -> BBbar Events Tagged by B- -> D0 l- nubar (X) Decays (open access)

Branching Fraction for B+ -> pi0 l+ nu, Measured in Upsilon (4S) -> BBbar Events Tagged by B- -> D0 l- nubar (X) Decays

We report a preliminary branching fraction of (1.80 {+-} 0.37{sub stat.} {+-} 0.23{sub syst.}) x 10{sup -4} for the charmless exclusive semileptonic B{sup +} {yields} {pi}{sup 0}{ell}{sup +}{nu} decay, where {ell} can be either a muon or an electron. This result is based on data corresponding to an integrated luminosity of 81 fb{sup -1} collected at the {Upsilon}(4S) resonance with the BABAR detector. The analysis uses B{bar B} events that are tagged by a B meson reconstructed in the semileptonic B{sup -} {yields} D{sup 0}{ell}{sup -}{bar {nu}}(X) decays, where X can be either a {gamma} or a {pi}{sup 0} from a D* decay.
Date: June 29, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
System: The UNT Digital Library
Branching Fraction for B0 -> pi- l+ nu and Determination of |Vub| in Upsilon(4S) -> B0 B0bar Events Tagged by B0bar -> D(*)+ l- nubar (open access)

Branching Fraction for B0 -> pi- l+ nu and Determination of |Vub| in Upsilon(4S) -> B0 B0bar Events Tagged by B0bar -> D(*)+ l- nubar

We report preliminary results from a study of the charmless exclusive semileptonic decay B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu} based on the data collected at the {Upsilon}(4S) resonance using the BABAR detector at SLAC. The analysis uses events in which the signal B meson recoils against a B meson that has been reconstructed in a semileptonic decay {bar B}{sup 0} {yields} D{sup (*)+}{ell}{sup -}{bar {nu}}. We extract the total branching fraction {Beta}(B{sup 0} {yields} {pi}{sup -}{ell}{sup +}{nu}) = (1.03 {+-} 0.25{sub stat.} {+-} 0.13{sub syst.}) x 10{sup -4} and the partial branching fractions in three bins of q{sup 2}, the invariant mass squared of the lepton-neutrino system. From the partial branching fractions and theoretical predictions for the form factors, we determine the magnitude of the CKM matrix element |V{sub ub}|. We find |V{sub ub}| = (3.3 {+-} 0.4{sub stat.} {+-} 0.2{sub syst.} {sub -0.4}{sup +0.8}FF) x 10{sup -3}, where the last error is due to normalization of the form factor.
Date: June 29, 2005
Creator: Aubert, B.; Barate, R.; Boutigny, D.; Couderc, F.; Karyotakis, Y.; Lees, J. P. et al.
System: The UNT Digital Library
Calibration of symmetric and non-symmetric errors for interferometry of ultra-precise imaging systems (open access)

Calibration of symmetric and non-symmetric errors for interferometry of ultra-precise imaging systems

The azimuthal Zernike coefficients for shells of Zernike functions with shell numbers n<N may be determined by making measurements at N equally spaced rotational positions. However, these measurements do not determine the coefficients of any of the purely radial Zernike functions. Label the circle that the azimuthal Zernikes are measured in as circle A. Suppose that the azimuthal Zernike coefficients for n<N are also measured in a smaller circle B which is inside circle A but offset so that it is tangent to circle A and so that it has the center of circle A just inside its circular boundary. The diameter of circle B is thus only slightly larger than half the diameter of circle A. From these two sets of measurements, all the Zernike coefficients may be determined for n<N. However, there are usually unknown small rigid body motions of the optic between measurements. Then all the Zernike coefficients for n<N except for piston, tilts, and focus may be determined. We describe the exact mathematical algorithm that does this and describe an interferometer which measures the complete wavefront from pinholes in pinhole aligners. These pinhole aligners are self-contained units which include a fiber optic, focusing optics, and a …
Date: June 29, 2005
Creator: Phillion, D. W.; Sommargren, G. E.; Johnson, M. A.; Decker, T. A.; Taylor, J. S.; Gomie, Y et al.
System: The UNT Digital Library
Ceramic Plutonium Target Development for the MASHA Separator for the Synthesis of Element 114 (open access)

Ceramic Plutonium Target Development for the MASHA Separator for the Synthesis of Element 114

We are currently developing a Pu ceramic target for the MASHA mass separator. MASHA will use a Pu ceramic target capable of tolerating temperatures up to 2000 C. Reaction products will diffuse out of the target into an ion source, and transported through the separator to a position-sensitive focal-plane detector array for mass identification. Experiments on MASHA will allow us to make measurements that will cement our identification of element 114 and provide data for future experiments on chemical properties of the heaviest elements. In this study (Sm,Zr)O{sub 2-x} ceramics are produced and evaluated for studies on the production of Pb (homolog of element 114) by the reaction of Ca on Sm. This work will provide an initial analysis on the feasibility of using a ZrO{sub 2}-PuO{sub 2} as a target for the production of element 114.
Date: June 29, 2005
Creator: Shaughnessy, D A; Wilk, P A; Moody, K J; Kenneally, J M; Wild, J F; Stoyer, M A et al.
System: The UNT Digital Library
Charm Physics at BaBar (open access)

Charm Physics at BaBar

Large production of the c{bar c} pairs and high integrated luminosity make the PEPII B Factory an excellent place for studying the charm hadrons. In this paper, we present a few most recent results from BaBar collaboration in charm sector.
Date: June 29, 2005
Creator: Chen, Chunhui
System: The UNT Digital Library
CIRCE, the Coherent Infrared Center at the ALS (open access)

CIRCE, the Coherent Infrared Center at the ALS

CIRCE (Coherent InfraRed CEnter) is a proposal for a new electron storage ring to be built at the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory (LBNL). The ring design is optimized for the generation of coherent synchrotron radiation (CSR) in the terahertz frequency range. Among others, CIRCE operation includes three interesting CSR modes: ultra stable, femtosecond laser slicing and broadband bursting. CSR allows CIRCE to generate an extremely high flux in the terahertz frequency region. The many orders of magnitude increase in the intensity over that presently achievable by conventional sources, has the potential to enable new science experiments. The characteristics of CIRCE and of the different modes of operation are described in this paper.
Date: June 29, 2004
Creator: Byrd, John M.; De Santis, Stefano; Jung, Jin-Young; Li, Derun; Martin, Michael C.; McKinney, W. et al.
System: The UNT Digital Library
Collisional Cooling of Negative Ion Beams (open access)

Collisional Cooling of Negative Ion Beams

Investigations have been conducted to determine the feasibility of using collisional cooling for reducing the energy spreads and, consequently, the emittances of negative-ion beams. We have designed a gas-filled RF-quadrupole ion cooler equipped with provisions for retarding energetic negative ion beams to energies below thresholds for electron detachment at injection and for re-acceleration to high energies after the cooling process. The device has been used to cool O{sup -} and F{sup -} ion beams with initial energy spreads, {Delta}E > 10 eV to final energy spreads, {Delta}E {approx} 2 eV FWHM. Overall transmission efficiencies of {approx}14% for F{sup -} beams have been obtained. Experimental results show that electron detachment is the major loss mechanism for negative ions.
Date: June 29, 2001
Creator: Liu, Y.
System: The UNT Digital Library
Commissioning of BL 7.2, the new diagnostic beam line at the ALS (open access)

Commissioning of BL 7.2, the new diagnostic beam line at the ALS

BL 7.2 is a new beamline at the Advanced Light Source (ALS) of the Lawrence Berkeley National Laboratory (LBNL) dedicated to electron beam diagnostics. The system, which is basically a hard x-ray pinhole camera, was installed in the storage ring in August 2003 and commissioning with the ALS electron beam followed immediately after. In this paper the commissioning results are presented together with the description of the relevant measurements performed for the beamline characterization.
Date: June 29, 2004
Creator: Sannibale, Fernando; Baum, Dennis; Biocca, Alan; Kelez, Nicholas; Nishimura, Toshiro; Scarvie, Tom et al.
System: The UNT Digital Library
Comparison of Design and Practices for Radiation Safety among Five Synchrotron Radiation Facilities (open access)

Comparison of Design and Practices for Radiation Safety among Five Synchrotron Radiation Facilities

There are more and more third-generation synchrotron radiation (SR) facilities in the world that utilize low emittance electron (or positron) beam circulating in a storage ring to generate synchrotron light for various types of experiments. A storage ring based SR facility consists of an injector, a storage ring, and many SR beamlines. When compared to other types of accelerator facilities, the design and practices for radiation safety of storage ring and SR beamlines are unique to SR facilities. Unlike many other accelerator facilities, the storage ring and beamlines of a SR facility are generally above ground with users and workers occupying the experimental floor frequently. The users are generally non-radiation workers and do not wear dosimeters, though basic facility safety training is required. Thus, the shielding design typically aims for an annual dose limit of 100 mrem over 2000 h without the need for administrative control for radiation hazards. On the other hand, for operational and cost considerations, the concrete ring wall (both lateral and ratchet walls) is often desired to be no more than a few feet thick (with an even thinner roof). Most SR facilities have similar operation modes and beam parameters (both injection and stored) for storage …
Date: June 29, 2005
Creator: Liu, James C.; Rokni, Sayed H.; Asano, Yoshihiro; Casey, William R. & Donahue, Richard J.
System: The UNT Digital Library
Comparison of Sensitivity Analysis Techniques in Monte Carlo Codes for Multi-Region Criticality Calculations (open access)

Comparison of Sensitivity Analysis Techniques in Monte Carlo Codes for Multi-Region Criticality Calculations

Recently, sensitivity and uncertainty (S/U) techniques have been used to determine the area of applicability (AOA) of critical experiments used for code and data validation. These techniques require the computation of energy-dependent sensitivity coefficients for multiple reaction types for every nuclide in each system included in the validation. The sensitivity coefficients, as used for this application, predict the relative change in the system multiplication factor due to a relative change in a given cross-section data component or material number density. Thus, a sensitivity coefficient, S, for some macroscopic cross section, {Sigma}, is expressed as S = {Sigma}/k {partial_derivative}k/{partial_derivative}{Sigma}, where k is the effective neutron multiplication factor for the system. The sensitivity coefficient for the density of a material is equivalent to that of the total macroscopic cross section. Two distinct techniques have been employed in Monte Carlo radiation transport codes for the computation of sensitivity coefficients. The first, and most commonly employed, is the differential sampling technique. The second is the adjoint-based perturbation theory approach. This paper briefly describes each technique and presents the results of a simple test case, pointing out discrepancies in the computed results and proposing a remedy to these discrepancies.
Date: June 29, 2001
Creator: Rearden, B. T.
System: The UNT Digital Library
Computational Design Studies for an Ion Extraction System for the Oak Ridge National Laboratory ECR Ion Source (open access)

Computational Design Studies for an Ion Extraction System for the Oak Ridge National Laboratory ECR Ion Source

A three-electrode system for optimally extracting, high-intensity, multi-charged ion beams from an all-permanent-magnet, ''volume''-type, ECR ion source, has been computationally designed. Beams of highest quality and transportability are extracted whenever the angular divergence is minimum. Under this condition, the plasma boundary has an optimum curvature, the angular divergence is consequently minimum; the perveance, the extraction gap, and the current density each have optimum values. Results obtained from computational simulation studies of the extraction optics are found to closely agree with those derived from elementary analytical theory for extraction of space-charge-dominated beams.
Date: June 29, 2001
Creator: Zaim, H.
System: The UNT Digital Library
Computational Needs for Muon Accelerators. (open access)

Computational Needs for Muon Accelerators.

Muon accelerators contain beam lines and components which are unlike any found in existing accelerators. Production of the muons requires targets for beams with powers which are at or beyond what has currently been achieved. Many subsystems use solenoid focusing systems where at any given point, several magnets have a significant influence. The beams that are transported can have energy spreads of {+-}30% or more. The required emittances necessitate accurate tracking of particles with angles of tenths of a radian and which are positioned almost at the edge of the beam pipe. Tracking must be done not only in vacuum, but also in materials; therefore, statistical fluctuations must also be included. Design and simulation of muon accelerators requires software which can: accurately simulate the dynamics of solid and liquid targets under proton bombardment; predict the production of particles from these targets; accurately compute magnetic fields based on either a real magnet design or a model which includes end fields; and accurately design and simulate a beam line where the transported beam satisfies the above specifications and the beam line contains non-standard, overlapping elements. The requirements for computational tools will be discussed, the capabilities of existing tools will be described and …
Date: June 29, 2004
Creator: Berg, J. S.
System: The UNT Digital Library
Computer Generated Inputs for NMIS Processor Verification (open access)

Computer Generated Inputs for NMIS Processor Verification

Proper operation of the Nuclear Identification Materials System (NMIS) processor can be verified using computer-generated inputs [BIST (Built-In-Self-Test)] at the digital inputs. Preselected sequences of input pulses to all channels with known correlation functions are compared to the output of the processor. These types of verifications have been utilized in NMIS type correlation processors at the Oak Ridge National Laboratory since 1984. The use of this test confirmed a malfunction in a NMIS processor at the All-Russian Scientific Research Institute of Experimental Physics (VNIIEF) in 1998. The NMIS processor boards were returned to the U.S. for repair and subsequently used in NMIS passive and active measurements with Pu at VNIIEF in 1999.
Date: June 29, 2001
Creator: Mullens, J. A.; Breeding, J. E.; McEvers, J. A.; Wysor, R. W.; Chiang, L. G.; Lenarduzzi, J. R. et al.
System: The UNT Digital Library
Coordination of software-development activities among sites that are geographically separated (open access)

Coordination of software-development activities among sites that are geographically separated

The Department of Defense is sponsoring development of a centralized, integrated database, which will be a repository international surface cargo movement data. Scheduled for implementation surface in early 1994, the system will include a relational database management system, processing modules, and complex communication components. Four geographically separated sites are involved with development. Design and development of a major computer system is never simple, but when design and development occur at multiple sites, the problems are compounded, especially when the timeframe for project completion is extremely tight. Issues such as identical developmental platforms and communications strategies must be addressed. A design plan must be strictly followed to ensure consistency and to coordinate integration of modules developed at different sites.
Date: June 29, 1993
Creator: Truett, L. F.; Loftis, J. P.; Shipe, P. C.; Faby, E. Z. & Grubb, J. W.
System: The UNT Digital Library