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

Description: 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 … more
Date: June 29, 1998
Creator: Lochter, Andre; Navre, Marc; Werb, Zena & Bissell, Mina J
Partner: UNT Libraries Government Documents Department
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Large N elliptic genus and AdS/CFT Correspondence

Description: According to one of Maldacena's dualities, type IIB string theory on AdS{sub 3} x S{sup 3} x K3 is equivalent to a certain N = (4, 4) superconformal field theory. In this note we compute the elliptic genus of the boundary theory in the supergravity approximation. A finite quantity is obtained once we introduce a particular exclusion principle. In the regime where the supergravity approximation is reliable, we find exact agreement with the elliptic genus of a sigma model with target space K3{sup… more
Date: December 29, 1998
Creator: de Boer, Jan
Partner: UNT Libraries Government Documents Department
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Transmission electron microscopy study of cascade collapse in copper during in-situ ion-irradiation at elevated temperatures.

Description: The basic mechanisms driving the collapse of point defects produced in collision cascades are investigated by transmission electron microscope (TEM) characterization of defect microstructure produced in fcc-Cu irradiated with low-fluences of heavy (100 keV Kr) ions at elevated temperature (23--600 C). Areal defect yields are determined from direct TEM observation of the total defect production integrated over the duration of the in-situ ion-irradiation. They are unequivocally demonstrated to de… more
Date: January 29, 1998
Creator: Daulton, T. L.; Kirk, M. A. & Rehn, L. E.
Partner: UNT Libraries Government Documents Department
open access

Sixth International Conference on Precipitation: Predictability of Rainfall at the Various Scales. Abstracts

Description: This volume contains abstracts of the papers presented at the Sixth International Conference on Precipitation: Predictability of Rainfall at the various scales, held at the Mauna Lani Bay and Bungalows, Hawaii, June 29 - July 1, 1998. The main goal of the conference was to bring together meteorologists, hydrologists, mathematicians, physicists, statisticians, and all others who are interested in fundamental principles governing the physical processes of precipitation. The results of the previou… more
Date: June 29, 1998
Partner: UNT Libraries Government Documents Department
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Induced Recrystallization of CdTe Thin Films Deposited by Close-Spaced Sublimation

Description: We have deposited CdTe thin films by close-spaced sublimation at two different temperature ranges. The films deposited at the lower temperature partially recrystallized after CdCl{sub 2} treatment at 350 C and completely recrystallized after the same treatment at 400 C. The films deposited at higher temperature did not recrystallize at these two temperatures. These results confirmed that the mechanisms responsible for changes in physical properties of CdTe films treated with CdCl{sub 2} are rec… more
Date: October 29, 1998
Creator: Moutinho, H. R.; Dhere, R. G.; Al-Jassim, M. M.; Levi, D. H.; Kazmerski, L. L. (National Renewable Energy Laboratory) & Mayo, B. (Southern University and A&M College, LA)
Partner: UNT Libraries Government Documents Department
open access

Integrated models for plasma/material interaction during loss of plasma confinement.

Description: A comprehensive computer package, High Energy Interaction with General Heterogeneous Target Systems (HEIGHTS), has been developed to evaluate the damage incurred on plasma-facing materials during loss of plasma confinement. The HEIGHTS package consists of several integrated computer models that follow the start of a plasma disruption at the scrape-off layer (SOL) through the transport of the eroded debris and splashed target materials to nearby locations as a result of the energy deposited. The… more
Date: July 29, 1998
Creator: Hassanein, A.
Partner: UNT Libraries Government Documents Department
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Coupled neutronic and thermal-hydraulic code benchmark activities at the International Nuclear Safety Center.

Description: Two realistic benchmark problems are defined and used to assess the performance of coupled thermal-hydraulic and neutronic codes used in simulating dynamic processes in VVER-1000 and RBMK reactor systems. One of the problems simulates a design basis accident involving the ejection of three control and protection system rods from a VVER-1000 reactor. The other is based on a postulated rod withdrawal from an operating RBMK reactor. Preliminary results calculated by various codes are compared. Whi… more
Date: July 29, 1998
Creator: Podlazov, L. N.
Partner: UNT Libraries Government Documents Department
open access

Uranium and plutonium solution assays by transmission-corrected x-ray fluorescence

Description: We have developed an x-ray fluorescence analysis technique for uranium and plutonium solutions which compensates for variations in the absorption of the exciting gamma rays and fluorescent x-rays. We use {sup 57}Co to efficiently excite the K lines of the elements, and a mixed {sup 57}Co plus {sup 153}Gd transmission source to correct for variations in absorption. The absorption correction is a unique feature of our technique which permits accurate calibration with a single solution standard an… more
Date: July 29, 1998
Creator: Ruhter, W D & Ryon, R W
Partner: UNT Libraries Government Documents Department
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In-beam {gamma}-ray spectroscopy in the vicinity of {sup 100}Sn.

Description: In recent years, in-beam x-ray experiments supplied a vast amount of data on high-spin states in nuclei in the vicinity of {sup 100}Sn. The present contribution reviews spectroscopic information obtained recently for N {ge} 50 nuclei around {sup 100}Sn, with emphasis on isomer studies, and discusses selected results in the frame of the shell model.
Date: September 29, 1998
Creator: Seweryniak, D.
Partner: UNT Libraries Government Documents Department
open access

Electrometallurgical treatment of aluminum-based fuels.

Description: We have successfully demonstrated aluminum electrorefining from a U-Al-Si alloy that simulates spent aluminum-based reactor fuel. The aluminum product contains less than 200 ppm uranium. All the results obtained have been in agreement with predictions based on equilibrium thermodynamics. We have also demonstrated the need for adequate stirring to achieve a low-uranium product. Most of the other process steps have been demonstrated in other programs. These include uranium electrorefining, transu… more
Date: July 29, 1998
Creator: Willit, J. L.
Partner: UNT Libraries Government Documents Department
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Convergence estimates over the ABLE region during CASES-97 obtained from radar wind profiler and sodar data.

Description: Values of w calculated from the divergence of minisodar (MS) and radar wind profiler (RWP) horizontal wind profiles were found to agree quite well for an equilateral triangle of measurement sites located at the Argonne Boundary Layer Experiments (ABLE) facility. Values of w averaged over the daytime within the mixed layer were on the order of 0.5 cm/s. Correcting for height differences of 60-100 m among the three measurement sites separated by 63 km was helpful, particularly during windy condit… more
Date: September 29, 1998
Creator: Coulter, R. L.
Partner: UNT Libraries Government Documents Department
open access

Null-plane invariance of Hamiltonian null-plane dynamics.

Description: Relativistic Hamiltonian few-body dynamics [1,2] involves two unitary representations of the Poincare group on the Hilbert space H of physical states, with and without interactions. These two representations, U({Lambda}, a) and U{sub 0}({Lambda},a), coincide for a kinematic subgroup H. The ''Hamiltonians'' are the generators not in the Lie algebra of the kinematic subgroup. The kinematic subgroup of null-plane dynamics leaves the null-plane z {center_dot} x {triple_bond} x{sup 0} + x{sub 3} = 0… more
Date: July 29, 1998
Creator: Coester, F.
Partner: UNT Libraries Government Documents Department
open access

Vibratory response of a precision double-multi-layer monochromator positioning system using a generic modeling program with experimental verification.

Description: A generic vibratory response-modeling program has been developed as a tool for designing high-precision optical positioning systems. The systems are modeled as rigid-body structures connected by linear non-rigid elements such as complex actuators and bearings. The full dynamic properties of each non-rigid element are determined experimentally or theoretically, then integrated into the program as inertial and stiffness matrices. Thus, it is possible to have a suite of standardize structural elem… more
Date: July 29, 1998
Creator: Barraza, J.
Partner: UNT Libraries Government Documents Department
open access

Thermodynamic and nonstoichiometric behavior of the GdBa{sub 2}Cu{sub 3}O{sub x} system.

Description: Electromotive force (EMF) measurements of oxygen fugacities as a function of stoichiometry have been made on the GdBa{sub 2}Cu{sub 3}O{sub x} system in the temperature range {approximately}400-600 C by means of an oxygen titration technique with an yttria-stabilized zirconia electrolyte. Equations for the variation of oxygen partial pressure with composition and temperature have been derived from our EMF measurements. The shape of the 400 C isotherms as a function of oxygen stoichiometry for th… more
Date: September 29, 1998
Creator: Tetenbaum, M.
Partner: UNT Libraries Government Documents Department
open access

Laser beam welding of AZ31B-H24 magnesium alloy.

Description: The laser beam weldability of AZ31B magnesium alloy was examined with high power CW CO{sub 2} and pulsed Nd:YAG lasers. The low viscosity and surface tension of the melt pool make magnesium more difficult to weld than steel. Welding parameters necessary to obtain good welds were determined for both CW CO{sub 2} and pulsed Nd:YAG lasers. The weldability of the magnesium alloy was significantly better with the Nd:YAG laser. The cause of this improvement was attributed to the higher absorption of … more
Date: September 29, 1998
Creator: Leong, K. H.
Partner: UNT Libraries Government Documents Department
open access

Study of hyperon-nucleon interactions with d(e,e'K) reactions.

Description: The dependence of the d(e,e{prime}K{sup +}) reaction cross sections on the hyperon-nucleon interactions is investigated. It is shown that the data obtained with Longitudinal-Transverse separation or polarized photons can distinguish a class of Nijmegen models of hyperon-nucleon interactions which are {chi}{sup 2}-equivalent in fitting the existing 35 data points of hyperon-nucleon reactions.
Date: January 29, 1998
Creator: Lee, T. S. H.
Partner: UNT Libraries Government Documents Department
open access

Two-Phonon Excitations in <Sup>170</Sup>Er

Description: Recent experiments at the GEANIE/WNR facility and the University of Kentucky accelerator have yielded strong evidence for a two-gamma excitation in <sup>170</sup>Er. This new case can be added to a handful of previously identified examples of two-gamma vibrations, all of them discovered in this decade. In this paper the experimental evidence for a two-phonon excitation <sup>170</sup>Er is presented and the current state of understanding of these structures is reviewed in the context of this and… more
Date: September 29, 1998
Creator: Archer, D. E.; Becker, J. A.; Bernstein, L. A.; Garrett, P. E.; Johns, G. D.; Kadi, M. et al.
Partner: UNT Libraries Government Documents Department
open access

Thin-walled compliant plastic structures for meso-scale fluidic systems

Description: Thin-walled, compliant plastic structures for meso-scale fluidic systems were fabricated, tested and used to demonstrate valving, pumping, metering and mixing. These structures permit the isolation of actuators and sensors from the working fluid, thereby reducing chemical compatibility issues. The thin-walled, compliant plastic structures can be used in either a permanent, reusable system or as an inexpensive disposable for single-use assay systems. The implementation of valving, pumping, mixin… more
Date: December 29, 1998
Creator: Miles, R. R. & Schumann, D. L.
Partner: UNT Libraries Government Documents Department
open access

Engineering the use of green plants to reduce produced water disposal volume.

Description: In 1990, the Laboratory began an investigation into biological approaches for the reduction of water produced from oil and gas wells. In the spring of 1995, the Company began an on-site experiment at an oil/gas lease in Oklahoma using one of these approaches. The process, known as phytoremediation, utilizes the ability of certain salt tolerant plants to draw the produced water through their roots, transpire the water from their leaves, and thereby reduce overall water disposal volumes and costs… more
Date: January 29, 1998
Creator: Hinchman, R.; Mollock, G. N.; Negri, M. C. & Settle, T.
Partner: UNT Libraries Government Documents Department
open access

Neural Network Modeling of the Lithium/Thionyl Chloride Battery System

Description: Battery systems have traditionally relied on extensive build and test procedures for product realization. Analytical models have been developed to diminish this reliance, but have only been partially successful in consistently predicting the performance of battery systems. The complex set of interacting physical and chemical processes within battery systems has made the development of analytical models a significant challenge. Advanced simulation tools are needed to more accurately model batter… more
Date: October 29, 1998
Creator: Ingersoll, David; Jungst, Rudolph G.; O'Gorman, Christian C. & Paez, Thomas L.
Partner: UNT Libraries Government Documents Department
open access

Development system performance issues of the NIF master oscillator and pulse forming networking

Description: A crucial step in the development of a complex laser system is initial testing of an integrated system. Issues arise at the system level which are not easily observed in component level testing. The NIF master oscillator room (MOR) contains a network of fiber and integrated optic components which can interact, potentially reducing system performance. Here we present some of the system problems we have seen in integrated tests and our solutions. Issues include ASE in the fiber amplifiers, filter… more
Date: October 29, 1998
Creator: Browning, D; Dreifuerst, G; Penko, F; Rothenberg, J & Wilcox, R
Partner: UNT Libraries Government Documents Department
open access

Modeling of laser knife-edge and pinhole experiments

Description: We describe simulations of experiments involving laser illumination of a metallic knife edge in the Optical Sciences Laboratory (OSL) at LLNL, and pinhole closure in the Beamlet experiment at LLNL. The plasma evolution is modeled via LASNEX. In OSL, the calculated phases of a probe beam are found to exhibit the same behavior as in experiment but to be consistently larger. The motion of a given phase � contour tends to decelerate at high intensities. At fixed intensity, the speed decreases with … more
Date: June 29, 1998
Creator: Auerbach, J M; Boley, C D; Estabrook, K G; Feit, M D & Rubenchik, A M
Partner: UNT Libraries Government Documents Department
open access

High gain preamplifier module (PAM) engineering prototype for the National Ignition Facility (NIF) laser system

Description: We describe recent results and developments in the preamplifier module (PAM) engineering prototype located in NIF� s front end or Optical Pulse Generation (OPG) system. This prototype uses the general laser design developed on a physics testbed and integrates NIP type packaging as well as controls and diagnostics. We will present laser, mechanical and electrical hardware designed and built to date as well as laser energetics measurements.
Date: October 29, 1998
Creator: Braucht, J; Browning, D; Crane, J K; Crawford, J; Deadrick, F J; Hawkins, S et al.
Partner: UNT Libraries Government Documents Department
open access

Neutronics issues and inertial fusion energy: a summary of findings

Description: We have analyzed and compared five major inertial fusion energy (IFE) and two representative magnetic fusion energy (MFE) power plant designs for their environment, safety, and health (ES&H) characteristics. Our work has focussed upon the neutronics of each of the designs and the resulting radiological hazard indices. The calculation of a consistent set of hazard indices allows comparisons to be made between the designs. Such comparisons enable identification of trends in fusion ES&H characteri… more
Date: May 29, 1998
Creator: Latkowski, J. F.
Partner: UNT Libraries Government Documents Department
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