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Downregulation of Protein 4.1R impairs centrosome function,bipolar spindle organization and anaphase (open access)

Downregulation of Protein 4.1R impairs centrosome function,bipolar spindle organization and anaphase

Centrosomes nucleate and organize interphase MTs and areinstrumental in the assembly of the mitotic bipolar spindle. Here wereport that two members of the multifunctional protein 4.1 family havedistinct distributions at centrosomes. Protein 4.1R localizes to maturecentrioles whereas 4.1G is a component of the pericentriolar matrixsurrounding centrioles. To selectively probe 4.1R function, we used RNAinterference-mediated depletion of 4.1R without decreasing 4.1Gexpression. 4.1R downregulation reduces MT anchoring and organization atinterphase and impairs centrosome separation during prometaphase.Metaphase chromosomes fail to properly condense/align and spindleorganization is aberrant. Notably 4.1R depletion causes mislocalizationof its binding partner NuMA (Nuclear Mitotic Apparatus Protein),essential for spindle pole focusing, and disrupts ninein. Duringanaphase/telophase, 4.1R-depleted cells have lagging chromosomes andaberrant MT bridges. Our data provide functional evidence that 4.1R makescrucial contributions to centrosome integrity and to mitotic spindlestructure enabling mitosis and anaphase to proceed with the coordinatedprecision required to avoid pathological events.
Date: March 17, 2006
Creator: Spence, Jeffrey R.; Go, Minjoung M.; Bahmanyar, S.; Barth,A.I.M. & Krauss, Sharon Wald
Object Type: Article
System: The UNT Digital Library
Drop Simulation of 6M Drum with Locking-Ring Closure and Liquid Contents (open access)

Drop Simulation of 6M Drum with Locking-Ring Closure and Liquid Contents

This paper presents the dynamic simulation of the 6M drum with a locking-ring type closure subjected to a 4.9-foot drop. The drum is filled with water to 98 percent of overflow capacity. A three dimensional finite-element model consisting of metallic, liquid and rubber gasket components is used in the simulation. The water is represented by a hydrodynamic material model in which the material's volume strength is determined by an equation of state. The explicit numerical method based on the theory of wave propagation is used to determine the combined structural response to the torque load for tightening the locking-ring closure and to the impact load due to the drop.
Date: April 17, 2006
Creator: Wu, T.
Object Type: Article
System: The UNT Digital Library
Dynamic Simulation of Shipping Package Subjected to Torque Load and Sequential Impacts (open access)

Dynamic Simulation of Shipping Package Subjected to Torque Load and Sequential Impacts

A numerical technique has been developed to simulate the structural responses of radioactive material packaging components requiring closure-tightening torque to the scenarios of the hypothetical accident conditions (HAC) defined in the Code of Federal Regulations Title 10 part 71 (10CFR 71). A rigorous solution to this type of problem poses a considerable mathematical challenge. Conventional methods for evaluating the residue stresses due to the torque load are either inaccurate or not applicable to dynamic analyses. In addition, the HAC events occur sequentially and the cumulative damage to the package needs to be evaluated. Commonly, individual HAC events are analyzed separately and the cumulative damage is not addressed. As a result, strict compliance of the package with the requirements specified in 10CFR 71 is usually demonstrated by physical testing. The proposed technique utilizes the combination of kinematic constraints, rigid-body motions and structural deformations to overcome some of the difficulties encountered in modeling the effect of cumulative damage in numerical solutions. The analyses demonstrating use of this technique were performed to determine the cumulative damage of torque preload, a 30-foot drop, a 30-foot dynamic crush and a 40-inch free fall onto a mild steel pipe.
Date: April 17, 2006
Creator: Wu, T.
Object Type: Article
System: The UNT Digital Library
Dystroglycan loss disrupts polarity and beta-casein induction inmammary epithelial cells by perturbing laminin anchoring (open access)

Dystroglycan loss disrupts polarity and beta-casein induction inmammary epithelial cells by perturbing laminin anchoring

Precise contact between epithelial cells and their underlying basement membrane is critical to the maintenance of tissue architecture and function. To understand the role that the laminin receptor dystroglycan (DG) plays in these processes, we assayed cell responses to laminin-111 following conditional ablation of DG expression in cultured mammary epithelial cells (MECs). Strikingly, DG loss disrupted laminin-111-induced polarity and {beta}-casein production, and abolished laminin assembly at the step of laminin binding to the cell surface. DG re-expression restored these deficiencies. Investigations of mechanism revealed that DG cytoplasmic sequences were not necessary for laminin assembly and signaling, and only when the entire mucin domain of extracellular DG was deleted did laminin assembly not occur. These results demonstrate that DG is essential as a laminin-111 co-receptor in MECs that functions by mediating laminin anchoring to the cell surface, a process that allows laminin polymerization, tissue polarity, and {beta}-casein induction. The observed loss of laminin-111 assembly and signaling in DG-/-MECs provides insights into the signaling changes occurring in breast carcinomas and other cancers, where DG's laminin-binding function is frequently defective.
Date: February 17, 2006
Creator: Weir, M. Lynn; Oppizzi, Maria Luisa; Henry, Michael D.; Onishi,Akiko; Campbell, Kevin P.; Bissell, Mina J. et al.
Object Type: Article
System: The UNT Digital Library
Early Birds - January 2006 (open access)

Early Birds - January 2006

Early Birds - January 2006.
Date: February 17, 2006
Creator: United States. Defense Base Closure and Realignment Commission.
Object Type: Text
System: The UNT Digital Library
ECO2N - A New TOUGH2 Fluid Property Module for Studies of CO2Storage in Saline Aquifers (open access)

ECO2N - A New TOUGH2 Fluid Property Module for Studies of CO2Storage in Saline Aquifers

ECO2N is a fluid property module for the TOUGH2 simulator (Version 2.0) that was designed for applications to geologic storage of CO{sub 2} in saline aquifers. It includes a comprehensive description of the thermodynamics and thermophysical properties of H{sub 2}O-NaCl-CO{sub 2} mixtures, that reproduces fluid properties largely within experimental error for the temperature, pressure and salinity conditions of interest(10 C {le} T {le} 110 C; P {le} 600 bar; salinity up to full halite saturation). Flow processes can be modeled isothermally or non-isothermally, and phase conditions represented may include a single (aqueous or CO{sub 2}-rich) phase, as well as two-phase mixtures. Fluid phases may appear or disappear in the course of a simulation, and solid salt may precipitate or dissolve. ECO2N can model super- as well as sub-critical conditions, but it does not make a distinction between liquid and gaseous CO{sub 2}. This paper highlights significant features of ECO2N, and presents illustrative applications.
Date: April 17, 2006
Creator: Pruess, Karsten & Spycher, Nicholas
Object Type: Article
System: The UNT Digital Library
Efficient computation of matched solutions of the KV envelope equations for periodic focusing lattices. (open access)

Efficient computation of matched solutions of the KV envelope equations for periodic focusing lattices.

A new iterative method is developed to numerically calculate the periodic, matched beam envelope solution of the coupled Kapchinskij-Vladimirskij (KV) equations describing the transverse evolution of a beam in a periodic, linear focusing lattice of arbitrary complexity. Implementation of the method is straightforward. It is highly convergent and can be applied to all usual parameterizations of the matched envelope solutions. The method is applicable to all classes of linear focusing lattices without skew couplings, and also applies to parameters where the matched beam envelope is strongly unstable. Example applications are presented for periodic solenoidal and quadrupole focusing lattices. Convergence properties are summarized over a wide range of system parameters.
Date: January 17, 2006
Creator: Lund, S M; Chilton, S H & Lee, E P
Object Type: Article
System: The UNT Digital Library
Elections in States Affected by Hurricanes Katrina and Rita (open access)

Elections in States Affected by Hurricanes Katrina and Rita

None
Date: October 17, 2006
Creator: Coleman, Kevin J. & Fischer, Eric A.
Object Type: Report
System: The UNT Digital Library
Embolectomy in a Rabbit Acute Arterial Occlusion Model Using a Novel Electromechanical Extraction Device (open access)

Embolectomy in a Rabbit Acute Arterial Occlusion Model Using a Novel Electromechanical Extraction Device

None
Date: July 17, 2006
Creator: Hartman, J.; Small, W., IV; Wilson, T. S.; Brock, J.; Buckley, P. R.; Benett, W. J. et al.
Object Type: Article
System: The UNT Digital Library
Emergency Communications: The Emergency Alert System (EAS) and All-Hazard Warnings (open access)

Emergency Communications: The Emergency Alert System (EAS) and All-Hazard Warnings

The Emergency Alert System (EAS) is built on a structure conceived in the 1950s when over-the-air broadcasting was the best-available technology for widely disseminating emergency alerts. Bills in the 109th Congress that would improve emergency alert systems, domestically and internationally, include S. 50 (Senator Inouye) and H.R. 296 (Representative Menendez); these bills were prompted by the tsunami disaster but include measures that also apply to the need for a better all-hazard warning system in the United States. The report summarizes the technology and administration of EAS and the National Oceanic and Atmospheric Administration (NOAA)/National Weather Service (NWS) all-hazard network, new programs in the Department of Homeland Security (DHS), and some of the key proposals for change.
Date: July 17, 2006
Creator: Moore, Linda K.
Object Type: Report
System: The UNT Digital Library
Emergency Communications: The Emergency Alert System (EAS) and All-Hazard Warnings (open access)

Emergency Communications: The Emergency Alert System (EAS) and All-Hazard Warnings

The Emergency Alert System (EAS) is one of several federally managed warning systems. The Federal Emergency Management Agency (FEMA) jointly administers EAS with the Federal Communications Commission (FCC), in cooperation with the National Weather Service (NWS), an organization within the National Oceanic and Atmospheric Administration (NOAA). The NOAA/NWS weather radio system has been upgraded to an all-hazard warning capability. This report summarizes the technology and administration of EAS and the NOAA/NWS all-hazard network, and some of the key proposals for change
Date: July 17, 2006
Creator: Moore, Linda K.
Object Type: Report
System: The UNT Digital Library
Emergency Communications: The Emergency Alert System (EAS) and All-Hazard Warnings (open access)

Emergency Communications: The Emergency Alert System (EAS) and All-Hazard Warnings

The Emergency Alert System (EAS) is one of several federally managed warning systems. The Federal Emergency Management Agency (FEMA) jointly administers EAS with the Federal Communications Commission (FCC), in cooperation with the National Weather Service (NWS), an organization within the National Oceanic and Atmospheric Administration (NOAA). The NOAA/NWS weather radio system has been upgraded to an all-hazard warning capability. This report summarizes the technology and administration of EAS and the NOAA/NWS all-hazard network, and some of the key proposals for change
Date: July 17, 2006
Creator: Moore, Linda K.
Object Type: Report
System: The UNT Digital Library
Enchanced hohlraum radiation drive through reduction of wall losses with high-Z mixture "cocktail" wall materials (open access)

Enchanced hohlraum radiation drive through reduction of wall losses with high-Z mixture "cocktail" wall materials

We present results from experiments, numerical simulations and analytic modeling, demonstrating enhanced hohlraum performance. Care in the fabrication and handling of hohlraums with walls consisting of high-Z mixtures (cocktails) has led to our demonstration, for the first time, of a significant increase in radiation temperature (up to +7eV at 300 eV) compared to a pure Au hohlraum, in agreement with predictions and ascribable to reduced wall losses. The data extrapolated to full NIF suggest we can expect an 18% reduction in wall loss for the current ignition design by switching to cocktail hohlraums, consistent with requirements for ignition with 1MJ laser energy.
Date: May 17, 2006
Creator: Schein, J; Jones, O; Rosen, M; Dewald, E; Glenzer, S; Gunther, J et al.
Object Type: Article
System: The UNT Digital Library
Energy flow in a hadronic cascade: Application to hadroncalorimetry (open access)

Energy flow in a hadronic cascade: Application to hadroncalorimetry

The hadronic cascade description developed in an earlierpaper is extended to the response of an idealized fine-sampling hadroncalorimeter. Calorimeter response is largely determined by the transferof energy E_e from the hadronic to the electromagnetic sector via \pi0production. Fluctuations in this quantity produce the "constant term" inhadron calorimeter resolution. The increase of its fractional mean, f_\rmem^0= \vevE_e/E, with increasing incident energy E causes the energydependence of the \pi/e ratio in a noncompensating calorimeter. The meanhadronic energy fraction, f_h0 = 1-f_\rm em0, was shown to scaleverynearly as a power law in E: f_h0 = (E/E_0)m-1, where E_0\approx1~;GeV forpions, and m\approx0.83. It follows that \pi/e=1-(1-h/e)(E/E_0)m-1, whereelectromagnetic and hadronic energy deposits are detected withefficiencies e and h, respectively. Fluctuations in these quantities,along with sampling fluctuations, are in corporated to give an overallunderstanding of resolution, which is different from the usual treatmentsin interesting ways. The conceptual framework is also extended to theresponse to jets and the difference between pi and presponse.
Date: May 17, 2006
Creator: Groom, Donald E.
Object Type: Article
System: The UNT Digital Library
Energy Prices and Tourism: Some Preliminary Observations (open access)

Energy Prices and Tourism: Some Preliminary Observations

None
Date: August 17, 2006
Creator: Gelb, Bernard A.
Object Type: Report
System: The UNT Digital Library
Enhanced Thermal Conductivity Oxide Fuels (open access)

Enhanced Thermal Conductivity Oxide Fuels

the purpose of this project was to investigate the feasibility of increasing the thermal conductivity of oxide fuels by adding small fractions of a high conductivity solid phase.
Date: January 17, 2006
Creator: Solomon, Alvin; Revankar, Shripad & McCoy, J. Kevin
Object Type: Report
System: The UNT Digital Library
Enhancing Scalability and Efficiency of the TOUGH2_MP for LinuxClusters (open access)

Enhancing Scalability and Efficiency of the TOUGH2_MP for LinuxClusters

TOUGH2{_}MP, the parallel version TOUGH2 code, has been enhanced by implementing more efficient communication schemes. This enhancement is achieved through reducing the amount of small-size messages and the volume of large messages. The message exchange speed is further improved by using non-blocking communications for both linear and nonlinear iterations. In addition, we have modified the AZTEC parallel linear-equation solver to nonblocking communication. Through the improvement of code structuring and bug fixing, the new version code is now more stable, while demonstrating similar or even better nonlinear iteration converging speed than the original TOUGH2 code. As a result, the new version of TOUGH2{_}MP is improved significantly in its efficiency. In this paper, the scalability and efficiency of the parallel code are demonstrated by solving two large-scale problems. The testing results indicate that speedup of the code may depend on both problem size and complexity. In general, the code has excellent scalability in memory requirement as well as computing time.
Date: April 17, 2006
Creator: Zhang, Keni & Wu, Yu-Shu
Object Type: Article
System: The UNT Digital Library
Estimating maximum sustainable injection pressure duringgeological sequestration of CO2 using coupled fluid flow andgeomechanical fault-slip analysis (open access)

Estimating maximum sustainable injection pressure duringgeological sequestration of CO2 using coupled fluid flow andgeomechanical fault-slip analysis

This paper demonstrates the use of coupled fluid flow andgeomechanical fault slip (fault reactivation) analysis to estimate themaximum sustainable injection pressure during geological sequestration ofCO2. Two numerical modeling approaches for analyzing faultslip areapplied, one using continuum stress-strain analysis and the other usingdiscrete fault analysis. The results of these two approaches to numericalfault-slip analyses are compared to the results of a more conventionalanalytical fault-slip analysis that assumes simplified reservoirgeometry. It is shown that the simplified analytical fault-slip analysismay lead to either overestimation or underestimation of the maximumsustainable injection pressure because it cannot resolve importantgeometrical factors associated with the injection induced spatialevolution of fluid pressure and stress. We conclude that a fully couplednumerical analysis can more accurately account for the spatial evolutionof both insitu stresses and fluid pressure, and therefore results in amore accurate estimation of the maximum sustainable CO2 injectionpressure.
Date: October 17, 2006
Creator: Rutqvist, J.; Birkholzer, J.; Cappa, F. & Tsang, C.-F.
Object Type: Article
System: The UNT Digital Library
EU Enlargement: Economic Implications for the United States (open access)

EU Enlargement: Economic Implications for the United States

This report discusses Economic Implications for the United States related to European Union(EU) enlargement.
Date: January 17, 2006
Creator: Cooper, William H.
Object Type: Report
System: The UNT Digital Library
EU-U.S. Economic Ties: Framework, Scope, and Magnitude. January 2006 (open access)

EU-U.S. Economic Ties: Framework, Scope, and Magnitude. January 2006

This report provides background information and analysis of the U.S.-EU economic relationship.
Date: January 17, 2006
Creator: Cooper, William H.
Object Type: Report
System: The UNT Digital Library
Evaluation and Characterization of In-Line Annealed Continuous Cast Aluminum Sheet (open access)

Evaluation and Characterization of In-Line Annealed Continuous Cast Aluminum Sheet

This R&D program will develop optimized, energy-efficient thermo-mechanical processing procedures for in-line annealing of continuously cast hot bands of two 5000 series aluminum alloys (5754 and 5052). The implementation of the R&D will result in the production of sheet with improved formability at high levels of productivity consistency and quality. The proposed R&D involves the following efforts: (1) Design and build continuous in-line annealing equipment for plant-scale trials; (2) Carry out plant-scale trials at Commonwealth Aluminum Corp.'s (CAC) plant in Carson; (3) Optimize the processing variables utilizing a metallurgical model for the kinetics of microstructure and texture evolution during thermo-mechanical processing; (4) Determine the effects of processing variables on the microstructure, texture, mechanical properties, and formability of aluminum sheet; (5) Develop design parameters for commercial implementation; and (6) Conduct techno-economic studies of the recommended process equipment to identify impacts on production costs. The research and development is appropriate for the domestic industry as it will result in improved aluminum processing capabilities and thus lead to greater application of aluminum in various industries including the automotive market. A teaming approach is critical to the success of this effort as no single company alone possesses the breadth of technical and financial resources …
Date: January 17, 2006
Creator: Das, Dr Subodh K.
Object Type: Report
System: The UNT Digital Library
Even Start: Funding Controversy (open access)

Even Start: Funding Controversy

None
Date: January 17, 2006
Creator: McCallion, Gail
Object Type: Report
System: The UNT Digital Library
Evidence for the Rare Decay B+ to Ds+ pi0 (open access)

Evidence for the Rare Decay B+ to Ds+ pi0

The authors have searched for the rare decay B{sup +} {yields} D{sub s}{sup +}{pi}{sup 0}. The analysis is based on a sample of 232 million {Upsilon}(4S) {yields} B{bar B} decays collected with the BABAR detector at the PEP-II e{sup +}e{sup -} storage ring. They find 19.6 signal events, corresponding to a significance of 4.7 {sigma}. The extracted signal yield including statistical and systematic uncertainties is 20.1{sub -6.0-1.5}{sup +6.8+0.4}, and they measure {Beta}(B{sup +} {yields} D{sub s}{sup +}{pi}{sup 0}) = (1.5{sub -0.4}{sup +0.5} {+-} 0.1 {+-} 0.2) x 10{sup -5}, where the first uncertainty is statistical, the second is systematic, and the last is due to the uncertainty on the D{sub s}{sup +} decay and its daughter decay branching fractions.
Date: November 17, 2006
Creator: Aubert, B.
Object Type: Article
System: The UNT Digital Library
Evolutionary Acquisition and Spiral Development in DOD Programs: Policy Issues for Congress (open access)

Evolutionary Acquisition and Spiral Development in DOD Programs: Policy Issues for Congress

The Department of Defense (DOD) in 2001 adopted a new approach for developing major weapon systems, called evolutionary acquisition with spiral development (EA/SD), as its preferred standard. EA/SD is intended to make DOD’s acquisition system more responsive to rapid changes in military needs. EA/SD poses potentially important challenges for Congress in carrying out its legislative functions, particularly committing to and effectively overseeing DOD weapon acquisition programs.
Date: May 17, 2006
Creator: Pagliano, Gary J. & O'Rourke, Ronald
Object Type: Report
System: The UNT Digital Library