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BNLs Synchrotron-radiation Research Hub for Characterizing Detection Materials and Devices for the NA22 Community (open access)

BNLs Synchrotron-radiation Research Hub for Characterizing Detection Materials and Devices for the NA22 Community

N/A
Date: April 9, 2013
Creator: Camarda, S. G.; Bolotnikov, A. E.; Cui, Y.; Hossain, A.; Roy, U.; Yang, G. et al.
System: The UNT Digital Library
Bottomonium Results By BaBar (open access)

Bottomonium Results By BaBar

Summary: Observation of {eta}{sub b}; Energy scan above {Upsilon}(4S); Search for {Upsilon} {r_arrow} {gamma}A{sup 0}, A{sup 0} {r_arrow} invisible; Hadronic transitions {Upsilon}(4S) {r_arrow} {Upsilon}(nS).
Date: April 3, 2012
Creator: Tosi, Silvano & /Genoa U. /INFN, Genoa
System: The UNT Digital Library
Brain-Targeted Proanthocyanidin Metabolites for Alzheimer's Disease Treatment (open access)

Brain-Targeted Proanthocyanidin Metabolites for Alzheimer's Disease Treatment

Article on brain-targeted proanthocyanidin metabolites for Alzheimer's disease treatment.
Date: April 11, 2012
Creator: Wang, Jun; Ferruzzi, Mario G.; Ho, Lap; Blount, Jack W.; Janle, Elsa M.; Gong, Bing et al.
System: The UNT Digital Library
Breast Cancer Cells in Three-dimensional Culture Display an Enhanced Radioresponse after Coordinate Targeting of Integrin ?5?1 and Fibronectin (open access)

Breast Cancer Cells in Three-dimensional Culture Display an Enhanced Radioresponse after Coordinate Targeting of Integrin ?5?1 and Fibronectin

Tactics to selectively enhance cancer radioresponse are of great interest. Cancer cells actively elaborate and remodel their extracellular matrix (ECM) to aid in survival and progression. Previous work has shown that {beta}1-integrin inhibitory antibodies can enhance the growth-inhibitory and apoptotic responses of human breast cancer cell lines to ionizing radiation, either when cells are cultured in three-dimensional laminin-rich ECM (3D lrECM) or grown as xenografts in mice. Here, we show that a specific {alpha} heterodimer of {beta}1-integrin preferentially mediates a prosurvival signal in human breast cancer cells that can be specifically targeted for therapy. 3D lrECM culture conditions were used to compare {alpha}-integrin heterodimer expression in malignant and nonmalignant cell lines. Under these conditions, we found that expression of {alpha}5{beta}1-integrin was upregulated in malignant cells compared with nonmalignant breast cells. Similarly, we found that normal and oncofetal splice variants of fibronectin, the primary ECM ligand of {alpha}5{beta}1-integrin, were also strikingly upregulated in malignant cell lines compared with nonmalignant acini. Cell treatment with a peptide that disrupts the interactions of {alpha}5{beta}1-integrin with fibronectin promoted apoptosis in malignant cells and further heightened the apoptotic effects of radiation. In support of these results, an analysis of gene expression array data from breast cancer …
Date: April 7, 2010
Creator: Nam, Jin-Min; Onodera, Yasuhito; Bissell, Mina J & Park, Catherine C
System: The UNT Digital Library
Bridging silyl groups in sigma-bond metathesis and [1, 2] shifts. An experimental and computational study of the reaction between cerium metallocenes and MeOSiMe3 (open access)

Bridging silyl groups in sigma-bond metathesis and [1, 2] shifts. An experimental and computational study of the reaction between cerium metallocenes and MeOSiMe3

The reaction of Cp'2CeH (Cp' = 1,2,4-(Me3C)3C5H2 ) with MeOSiMe3 gives Cp'2CeOMe and HSiMe3 and the reaction of the metallacycle, Cp'[(Me3C)2C5H2C(Me) 2CH2]Ce, with MeOSiMe3 yields Cp'2CeOCH2SiMe3, formed from hypothetical Cp'2CeCH2OSiMe3 by a [1, 2] shift also known as a silyl-Wittig rearrangement. Although both cerium products are alkoxides, they are formed by different pathways. DFT calculations on the reaction of the model metallocene, Cp2CeH, and MeOSiMe3 show that the lowest energy pathway is a H for OMe exchange at Ce that occurs by way of a sigma-bond metathesis transition state as SiMe3 exchanges partners. The formation of Cp2CeOCH2SiMe3 occurs by way of a low activation barrier [1, 2]shift of the SiMe3 group in Cp2CeCH2OSiMe3. Calculations on a model metallacycle, Cp[C5H4C(Me)2CH2]Ce, show that the metallacycle favors CH bond activation over sigma-bond metathesis involving the transfer of the SiMe3 group in good agreement with experiment. The sigma-bond metathesis involving the transfer of SiMe3 and the [1, 2]shift of SiMe3 reactions have in common a pentacoordinate silicon at the transition states. A molecular orbital analysis illustrates the connection between these two Si-O bond cleavage reactions and traces the reason why they occur for a silyl but not for an alkyl group to the difference …
Date: April 21, 2010
Creator: Werkema, Evan; Yahia, Ahmed; Maron, Laurent; Eisenstein, Odile & Andersen, Richard
System: The UNT Digital Library
Bringing the World to the Classroom through Videoconferencing and Project-based Learning (open access)

Bringing the World to the Classroom through Videoconferencing and Project-based Learning

Article describes a case study of a Texas-based school that implemented global projects to connect their students with many states and countries as a platform for integrating collaboration and communication skills, technology tools, and cultural diversity into an existing curriculum.
Date: April 23, 2014
Creator: Hopper, Susan B.
System: The UNT Digital Library
Building a Framework of Metadata Change to Support Knowledge Management (open access)

Building a Framework of Metadata Change to Support Knowledge Management

Article defining ways that metadata records might change (addition, deletion, or modification) and describing a study to evaluate multiple versions of selected records in the UNT Libraries' Digital Collections to observe the types and frequency of various changes.
Date: April 17, 2015
Creator: Zavalina, Oksana; Kizhakkethil, Priya; Alemneh, Daniel Gelaw; Phillips, Mark Edward & Tarver, Hannah
System: The UNT Digital Library
Calculating the probability of injected carbon dioxide plumes encountering faults (open access)

Calculating the probability of injected carbon dioxide plumes encountering faults

One of the main concerns of storage in saline aquifers is leakage via faults. In the early stages of site selection, site-specific fault coverages are often not available for these aquifers. This necessitates a method using available fault data to estimate the probability of injected carbon dioxide encountering and migrating up a fault. The probability of encounter can be calculated from areal fault density statistics from available data, and carbon dioxide plume dimensions from numerical simulation. Given a number of assumptions, the dimension of the plume perpendicular to a fault times the areal density of faults with offsets greater than some threshold of interest provides probability of the plume encountering such a fault. Application of this result to a previously planned large-scale pilot injection in the southern portion of the San Joaquin Basin yielded a 3% and 7% chance of the plume encountering a fully and half seal offsetting fault, respectively. Subsequently available data indicated a half seal-offsetting fault at a distance from the injection well that implied a 20% probability of encounter for a plume sufficiently large to reach it.
Date: April 1, 2011
Creator: Jordan, P.D.
System: The UNT Digital Library
Can Ionic Liquids Be Used As Templating Agents For Controlled Design of Uranium-Containing Nanomaterials? (open access)

Can Ionic Liquids Be Used As Templating Agents For Controlled Design of Uranium-Containing Nanomaterials?

Nanostructured uranium oxides have been prepared in ionic liquids as templating agents. Using the ionic liquids as reaction media for inorganic nanomaterials takes advantage of the pre-organized structure of the ionic liquids which in turn controls the morphology of the inorganic nanomaterials. Variation of ionic liquid cation structure was investigated to determine the impact on the uranium oxide morphologies. For two ionic liquid cations, increasing the alkyl chain length increases the aspect ratio of the resulting nanostructured oxides. Understanding the resulting metal oxide morphologies could enhance fuel stability and design.
Date: April 9, 2013
Creator: Visser, A.; Bridges, N. & Tosten, M.
System: The UNT Digital Library
Cardiovascular function, compliance, and connective tissue remodeling in the turtle, Trachemys scripta, following thermal acclimation (open access)

Cardiovascular function, compliance, and connective tissue remodeling in the turtle, Trachemys scripta, following thermal acclimation

This article suggests that cold acclimation alters cardiac shunting patterns with an increased R-L shunt flow, achieved through reducing systemic resistance and increasing systemic blood flow.
Date: April 13, 2016
Creator: Keen, Adam N.; Shiels, Holly A. & Crossley, Dane A., II
System: The UNT Digital Library
Causal Latent Semantic Analysis (cLSA): An Illustration (open access)

Causal Latent Semantic Analysis (cLSA): An Illustration

Article discussing an illustration of causal latent semantic analysis (cLSA).
Date: April 2011
Creator: Hossain, Muhammad Muazzem; Prybutok, Victor R. & Evangelopoulos, Nicholas
System: The UNT Digital Library
CdTeSe Crystals for Gamma-Ray Detectors (open access)

CdTeSe Crystals for Gamma-Ray Detectors

N/A
Date: April 9, 2013
Creator: U., Roy; James, R. B.; Kim, K. H. & Bolotnikov, A. E.
System: The UNT Digital Library
Ceramic HEPA Filter Program (open access)

Ceramic HEPA Filter Program

Potential benefits of ceramic filters in nuclear facilities: (1) Short term benefit for DOE, NRC, and industry - (a) CalPoly HTTU provides unique testing capability to answer questions for DOE - High temperature testing of materials, components, filter, (b) Several DNFSB correspondences and presentations by DNFSB members have highlighted the need for HEPA filter R and D - DNFSB Recommendation 2009-2 highlighted a nuclear facility response to an evaluation basis earthquake followed by a fire (aka shake-n-bake) and CalPoly has capability for a shake-n-bake test; (2) Intermediate term benefit for DOE and industry - (a) Filtration for specialty applications, e.g., explosive applications at Nevada, (b) Spin-off technologies applicable to other commercial industries; and (3) Long term benefit for DOE, NRC, and industry - (a) Across industry, strong desire for better performance filter, (b) Engineering solution to safety problem will improve facility safety and decrease dependence on associated support systems, (c) Large potential life-cycle cost savings, and (d) Facilitates development and deployment of LLNL process innovations to allow continuous ventilation system operation during a fire.
Date: April 30, 2012
Creator: Mitchell, M A; Bergman, W; Haslam, J; Brown, E P; Sawyer, S; Beaulieu, R et al.
System: The UNT Digital Library
Challenges of Algebraic Multigrid across Multicore Architectures (open access)

Challenges of Algebraic Multigrid across Multicore Architectures

Algebraic multigrid (AMG) is a popular solver for large-scale scientific computing and an essential component of many simulation codes. AMG has shown to be extremely efficient on distributed-memory architectures. However, when executed on modern multicore architectures, we face new challenges that can significantly deteriorate AMG's performance. We examine its performance and scalability on three disparate multicore architectures: a cluster with four AMD Opteron Quad-core processors per node (Hera), a Cray XT5 with two AMD Opteron Hex-core processors per node (Jaguar), and an IBM BlueGene/P system with a single Quad-core processor (Intrepid). We discuss our experiences on these platforms and present results using both an MPI-only and a hybrid MPI/OpenMP model. We also discuss a set of techniques that helped to overcome the associated problems, including thread and process pinning and correct memory associations.
Date: April 12, 2010
Creator: Baker, A H; Gamblin, T; Schulz, M & Yang, U M
System: The UNT Digital Library
Characterization of Detector-Grade CdTeSe Crystals (open access)

Characterization of Detector-Grade CdTeSe Crystals

N/A
Date: April 1, 2013
Creator: Camarda, G.; Yang, G.; Bolotnikov, A. E.; Cui, Y.; Hossain, A.; Kim, K. H. et al.
System: The UNT Digital Library
Characterizing Hydrogen Storage Media: Understanding the Interior Pore Structure of a Cu3BTC2 Metal-Organic Framework Infiltrated with NaAlH4 (open access)

Characterizing Hydrogen Storage Media: Understanding the Interior Pore Structure of a Cu3BTC2 Metal-Organic Framework Infiltrated with NaAlH4

Preliminary results support the nano-confinement of sodium alanate within the pores of a Cu{sub 3}BTC{sub 2} MOF substrate. Increased {sup 1}H and {sup 27}Al NMR T{sub 1} relaxation rates indicate a close proximity of infiltrated sodium alante to the paramagnetic Cu{sup 2+} ions on the BTC paddlewheel units. This is in support of the theory that an interaction due to the electronegative framework with the sodium alanate facilitates thermodynamically-favorable hydrogen adsorption and desorption. Further studies can elucidate the local electronic environment of the sodium ions, further supporting a charge-transfer mechanism as the driving force for thermodynamically-favorable hydrogen adsorption and desorption.
Date: April 15, 2010
Creator: Kirmiz, A; Bhakta, R K; Allendorf, M D; Majzoub, E H; Behrens, R & Herberg, J
System: The UNT Digital Library
Charge and fluence lifetime measurements of a dc high voltage GaAs photogun at high average current (open access)

Charge and fluence lifetime measurements of a dc high voltage GaAs photogun at high average current

GaAs-based dc high voltage photoguns used at accelerators with extensive user programs must exhibit long photocathode operating lifetime. Achieving this goal represents a significant challenge for proposed high average current facilities that must operate at tens of milliamperes or more. This paper describes techniques to maintain good vacuum while delivering beam, and techniques that minimize the ill effects of ion bombardment, the dominant mechanism that reduces photocathode yield of a GaAs-based dc high voltage photogun. Experimental results presented here demonstrate enhanced lifetime at high beam currents by: (a) operating with the drive laser beam positioned away from the electrostatic center of the photocathode, (b) limiting the photocathode active area to eliminate photoemission from regions of the photocathode that do not support efficient beam delivery, (c) using a large drive laser beam to distribute ion damage over a larger area, and (d) by applying a relatively low bias voltage to the anode to repel ions created within the downstream beam line. A combination of these techniques provided the best total charge extracted lifetimes in excess of 1000 C at dc beam currents up to 9.5 mA, using green light illumination of bulk GaAs inside a 100 kV photogun.
Date: April 1, 2011
Creator: J. Grames, R. Suleiman, P.A. Adderley, J. Clark, J. Hansknecht, D. Machie, M. Poelker, M.L. Stutzman
System: The UNT Digital Library
Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar (open access)

Charmless Hadronic B Decays into Vector, Axial Vector and Tensor Final States at BaBar

We present experimental measurements of branching fraction and longitudinal polarization fraction in charmless hadronic B decays into vector, axial vector and tensor final states with the final dataset of BABAR. Measurements of such kind of decays are a powerful tool both to test the Standard Model and search possible sources of new physics. In this document we present a short review of the last experimental results at BABAR concerning charmless quasi two-body decays in final states containing particles with spin 1 or spin 2 and different parities. This kind of decays has received considerable theoretical interest in the last few years and this particular attention has led to interesting experimental results at the current b-factories. In fact, the study of longitudinal polarization fraction f{sub L} in charmless B decays to vector vector (VV), vector axial-vector (VA) and axial-vector axial-vector (AA) mesons provides information on the underlying helicity structure of the decay mechanism. Naive helicity conservation arguments predict a dominant longitudinal polarization fraction f{sub L} {approx} 1 for both tree and penguin dominated decays and this pattern seems to be confirmed by tree-dominated B {yields} {rho}{rho} and B{sup +} {yields} {Omega}{rho}{sup +} decays. Other penguin dominated decays, instead, show a different …
Date: April 6, 2012
Creator: Gandini, Paolo
System: The UNT Digital Library
Charmonium Spectroscopy (X,Y,Z) at the B Factories (open access)

Charmonium Spectroscopy (X,Y,Z) at the B Factories

Since 2003 several states in the charmonium mass region were discovered. While in the conventional c{bar c} spectrum some states are missing, the number of states observed up to now is larger than empty spaces in the c{bar c} spectrum. This, together with other difficulties to explain observed states as a c{bar c} mesons triggered discussions on a possible exotic interpretations. In this proceedings we present current experimental status from B-factories of the so called X, Y and Z states.
Date: April 3, 2012
Creator: Kreps, Michal & U., /Karlsruhe
System: The UNT Digital Library
Chiral Steering of Molecular Organization in the Limit of Weak Adsorbate-Substrate Interactions: Enantiopure and Racemic Tartaric Acid Domains on Ag(111) (open access)

Chiral Steering of Molecular Organization in the Limit of Weak Adsorbate-Substrate Interactions: Enantiopure and Racemic Tartaric Acid Domains on Ag(111)

Article on the chiral steering of molecular organization in the limit of weak adsorbate-substrate interactions.
Date: April 23, 2010
Creator: Santagata, Nancy M.; Lakhani, Amit M.; Davis, Bryce F.; Luo, Pengshun; Buongiorno Nardelli, Marco & Pearl, Thomas P.
System: The UNT Digital Library
The cisd gene family regulates physiological germline apoptosis through ced-13 and the canonical cell death pathway in Caenorhabditis elegans (open access)

The cisd gene family regulates physiological germline apoptosis through ced-13 and the canonical cell death pathway in Caenorhabditis elegans

This article examines how the disruption of the cisd-1 gene function, using RNA interference (RNAi), or mutant alleles [cisd-1(tm4993) deletion mutant, cisd-1(pnIs27) insertion mutant] led to germline abnormalities including an increase in the number of cell corpses and distal tip cell migration defects.
Date: April 17, 2018
Creator: King, Skylar D.; Gray, Chipo F.; Song, Luhua; Nechushtai, Rachel; Gumienny, Tina L; Mittler, Ron et al.
System: The UNT Digital Library
CLARREO shortwave observing system simulation experiments of the twenty-first century: Simulator design and implementation (open access)

CLARREO shortwave observing system simulation experiments of the twenty-first century: Simulator design and implementation

Projected changes in the Earth system will likely be manifested in changes in reflected solar radiation. This paper introduces an operational Observational System Simulation Experiment (OSSE) to calculate the signals of future climate forcings and feedbacks in top-of-atmosphere reflectance spectra. The OSSE combines simulations from the Intergovernmental Panel on Climate Change (IPCC) Fourth Assessment Report for the NCAR Community Climate System Model (CCSM) with the MODTRAN radiative transfer code to calculate reflectance spectra for simulations of current and future climatic conditions over the 21st century. The OSSE produces narrowband reflectances and broadband fluxes, the latter of which have been extensively validated against archived CCSM results. The shortwave reflectance spectra contain atmospheric features including signals from water vapor, liquid and ice clouds, and aerosols. The spectra are also strongly influenced by the surface bidirectional reflectance properties of predicted snow and sea ice and the climatological seasonal cycles of vegetation. By comparing and contrasting simulated reflectance spectra based on emissions scenarios with increasing projected and fixed present-day greenhouse gas and aerosol concentrations, we find that prescribed forcings from increases in anthropogenic sulfate and carbonaceous aerosols are detectable and are spatially confined to lower latitudes. Also, changes in the intertropical convergence zone and …
Date: April 1, 2011
Creator: Feldman, Daniel R.; Algieri, Chris A.; Ong, Jonathan R. & Collins, William D.
System: The UNT Digital Library
Classical trajectory Monte Carlo code for simulating ion beam focusing or defocusing with magnetic elements modeled as current loops or current lines (open access)

Classical trajectory Monte Carlo code for simulating ion beam focusing or defocusing with magnetic elements modeled as current loops or current lines

Article describes a computational tool that can be used for designing magnetic focusing or defocusing systems. A fully three-dimensional classical trajectory Monte Carlo simulation has been developed.
Date: April 19, 2013
Creator: Lane, Ryan A. & Ordonez, Carlos A.
System: The UNT Digital Library
Cleanable and Hardcoat Coatings for Increased Durability of Silvered Polymeric Mirrors (open access)

Cleanable and Hardcoat Coatings for Increased Durability of Silvered Polymeric Mirrors

We have successfully developed coating formulations which significantly increasethe abrasion resistance of mirror films. We have demonstrated manufacturing scale-up of these films to full width andproduction volumes. Implementation of these films in commercial test sites is planned for Q2 2013(Abengoa, Gossamer Space Frames). This slide show outlines the background and objectives of the project, technical approach and results, and key lessons. It also presents the need and opportunity for reduction of costs for CSP and collectors. It also presents an approach for a large aperture parabolic trough collector with reflective film and a high concentration factor, including demonstration and results.
Date: April 1, 2013
Creator: Padiyath, Raghunath
System: The UNT Digital Library