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Beta4 integrin-dependent formation of polarized three-dimensionalarchitecture confers resistance to apoptosis in normal and malignantmammary epithelium (open access)

Beta4 integrin-dependent formation of polarized three-dimensionalarchitecture confers resistance to apoptosis in normal and malignantmammary epithelium

Tumor cells can evade chemotherapy by acquiring resistanceto apoptosis. We investigated the molecular mechanism whereby malignantand nonmalignant mammary epithelial cells become insensitive toapoptosis. We show that regardless of growth status formation ofpolarized, three-dimensional structures driven by basement membraneconfers protection to apoptosis in both nonmalignant and malignantmammary epithelial cells. By contrast, irrespective of their malignantstatus, nonpolarized structures are sensitive to induction of apoptosis.Resistance to apoptosis requires ligation of beta4 integrins, whichregulates tissue polarity, hemidesmosome formation and NFkB activation.Expression of beta4 integrin that lacks the hemidesmosome targetingdomain interferes with tissue polarity and NFkB activation and permitsapoptosis. These results indicate that integrin-induced polarity maydrive tumor cell resistance to apoptosis-inducing agents via effects onNFkB.
Date: August 27, 2002
Creator: Weaver, Valerie M.; Lelievre, Sophie; Lakins, Johnathon N.; Chrenek, Micah A.; Jones, Jonathan C.R.; Giancotti, Filippo et al.
Object Type: Article
System: The UNT Digital Library
Rains County Leader (Emory, Tex.), Vol. 115, No. 12, Ed. 1 Tuesday, August 27, 2002 (open access)

Rains County Leader (Emory, Tex.), Vol. 115, No. 12, Ed. 1 Tuesday, August 27, 2002

Weekly newspaper from Emory, Texas that includes local, state, and national news along with advertising.
Date: August 27, 2002
Creator: Hill, Earl Clyde, Jr.
Object Type: Newspaper
System: The Portal to Texas History
Modeling of Photonic Band Gap Crystals and Applications (open access)

Modeling of Photonic Band Gap Crystals and Applications

In this work, the authors have undertaken a theoretical approach to the complex problem of modeling the flow of electromagnetic waves in photonic crystals. The focus is to address the feasibility of using the exciting phenomena of photonic gaps (PBG) in actual applications. The authors start by providing analytical derivations of the computational electromagnetic methods used in their work. They also present a detailed explanation of the physics underlying each approach, as well as a comparative study of the strengths and weaknesses of each method. The Plane Wave expansion, Transfer Matrix, and Finite Difference time Domain Methods are addressed. They also introduce a new theoretical approach, the Modal Expansion Method. They then shift the attention to actual applications. They begin with a discussion of 2D photonic crystal wave guides. The structure addressed consists of a 2D hexagonal structure of air cylinders in a layered dielectric background. Comparison with the performance of a conventional guide is made, as well as suggestions for enhancing it. The studies provide an upper theoretical limit on the performance of such guides, as they assumed no crystal imperfections and non-absorbing media. Next, they study 3D metallic PBG materials at near infrared and optical wavelengths. The main …
Date: August 27, 2002
Creator: El-Kady, Ihab Fathy
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Organusulfur Catalysis With Reduced Molybdenum Sulfides Containing the Mo6S8 Cluster (open access)

Organusulfur Catalysis With Reduced Molybdenum Sulfides Containing the Mo6S8 Cluster

Industrial synthesis of sulfur-containing organic chemicals basically focuses on the broad categories of mercaptans (thiols), alkylsulfides (thioethers), polysulfides, and thiophenes. Of the organo-sulfur compounds produced, by far the most important in terms of quantities produced is methyl mercaptan (methanethiol or MeSH), which is produced mainly for the downstream production of methionine and methanesulfonyl chloride. Higher thiols are also used in the manufacture of rubber and plastics as polymerization regulators, chain transfer agents, or initiators. Other important organosulfur chemicals are dimethyl sulfide (DMS) and dimethyl disulfide (DMDS), both of which are used extensively for presulfiding of industrial hydroprocessing catalysts, and substituted thiophenes which are used as intermediates for production of agrochemicals, dyes, and pharmaceuticals. Thiols are produced commercially at the rate of about 10{sup 4} ton/yr from hydrogen sulfide (H{sub 2}S) and alcohols or olefins, using homogeneous free-radical synthesis, or heterogeneous catalysts based on solid acids or supported metal oxides and/or sulfides. Despite this large production rate, and the industrial importance of the organosulfur compounds, only limited research has been devoted to the development of new catalytic materials for their synthesis. Additionally, for most organosulfur catalytic reactions, only limited information exists about reaction mechanisms, active sites, adsorbed surface species, and especially …
Date: August 27, 2002
Creator: Paskach, Thomas Jay
Object Type: Thesis or Dissertation
System: The UNT Digital Library
IMPROVEMENT OF WEAR COMPONENT'S PERFORMANCE BY UTILIZING ADVANCED MATERIALS AND NEW MANUFACTURING TECHNOLOGIES: CASTCON PROCESS FOR MINING APPLICATIONS (open access)

IMPROVEMENT OF WEAR COMPONENT'S PERFORMANCE BY UTILIZING ADVANCED MATERIALS AND NEW MANUFACTURING TECHNOLOGIES: CASTCON PROCESS FOR MINING APPLICATIONS

The project has seen quite a bit of activity in this quarter, highlighted by the fabrication of a bit insert for field testing. In addition: (1) Several alternative process techniques were attempted to prevent bloating, cracking and delamination of FM material that occurs during binder burnout. The approaches included fabrication of FM material by three pass extrusion and warm isostatic pressing of green material, slow and confined burnouts as well as, burnout of thin plate instead of rod stock. Happily, a confined burnout followed by HIPing, produced FM button inserts without bloating or delamination. (2) Four rock bit inserts were produced from FM material and are ready for use on blast hole bits in the field. (3) Six of the project participants from Michigan Technological University, Advanced Ceramic Manufacturing, and The Robbins Group visited the Superior Rock Bit Company in Minnesota and planned the field test of FM inserts.
Date: August 27, 2002
Creator: Huang, Xiaodi & Gertsch, Richard
Object Type: Report
System: The UNT Digital Library
THERMAL, OPTIMIZATION OF POLYBENZIMIDAZOLE MENISCUS MEMBRANES FOR THE SEPARATION OF HYDROGREN, METHANE, AND CARBON DIOXIDE. (open access)

THERMAL, OPTIMIZATION OF POLYBENZIMIDAZOLE MENISCUS MEMBRANES FOR THE SEPARATION OF HYDROGREN, METHANE, AND CARBON DIOXIDE.

None
Date: August 27, 2002
Creator: DYE, ROBERT C; PESIRI, DAVID R & JORGENSEN, BETTY S
Object Type: Article
System: The UNT Digital Library
Development of Novel Polymeric Materials for Gene Therapy and pH-Sensitive Drug Delivery: Modeling, Synthesis, Characterization, and Analysis (open access)

Development of Novel Polymeric Materials for Gene Therapy and pH-Sensitive Drug Delivery: Modeling, Synthesis, Characterization, and Analysis

The underlying theme of this thesis is the use of polymeric materials in bioapplications. Chapters 2-5 either develop a fundamental understanding of current materials used for bioapplications or establish protocols and procedures used in characterizing and synthesizing novel materials. In chapters 6 and 7 these principles and procedures are applied to the development of materials to be used for gene therapy and drug delivery. Chapter one is an introduction to the ideas that will be necessary to understand the subsequent chapters, as well as a literature review of these topics. Chapter two is a paper that has been published in the ''Journal of Controlled Release'' that examines the mechanism of drug release from a polymer gel, as well as experimental design suggestions for the evaluation of water soluble drug delivery systems. Chapter three is a paper that has been published in the ''Journal of Pharmaceutical Sciences'' that discusses the effect ionic salts have on properties of the polymer systems examined in chapter two. Chapter four is a paper published in the Materials Research Society Fall 2000 Symposium Series dealing with the design and synthesis of a pH-sensitive polymeric drug delivery device. Chapter five is a paper that has been published …
Date: August 27, 2002
Creator: Anderson, Brian Curtis
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Magnetic X-Ray Scattering Study of GdCo2Ge2 and NdCo2Ge2 (open access)

Magnetic X-Ray Scattering Study of GdCo2Ge2 and NdCo2Ge2

The results of magnetic x-ray resonant exchange scattering (XRES) experiments are important to the development of an understanding of magnetic interactions in materials. The advantages of high Q resolution, polarization analysis, and the ability to study many different types of materials make it a vital tool in the field of condensed matter physics. Though the concept of XRES was put forth by Platzman and Tzoar in 1970, the technique did not gain much attention until the work of Gibbs and McWhan et al. in 1988. Since then, the technique of XRES has grown immensely in use and applicability. Researchers continue to improve upon the procedure and detection capabilities in order to study magnetic materials of all kinds. The XRES technique is particularly well suited to studying the rare earth metals because of the energy range involved. The resonant L edges of these elements fall between 5-10 KeV. Resonant and nonresonant x-ray scattering experiments were performed in order to develop an understanding of the magnetic ordering in GdCo{sub 2}Ge{sub 2} and NdCo{sub 2}Ge{sub 2}.
Date: August 27, 2002
Creator: Good, William
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Establishment of an Industry-Driven Consortium Focused on Improving the Production Performance of Domestic Stripper Wells Quarterly Report (open access)

Establishment of an Industry-Driven Consortium Focused on Improving the Production Performance of Domestic Stripper Wells Quarterly Report

The Pennsylvania State University, under contract to the U.S. Department of Energy, National Energy Technology Laboratory will establish, promote, and manage a national industry-driven Stripper Well Consortium (SWC) that will be focused on improving the production performance of domestic petroleum and/or natural gas stripper wells. The consortium creates a partnership with the U.S. petroleum and natural gas industries and trade associations, state funding agencies, academia, and the National Energy Technology Laboratory. This report serves as the sixth quarterly technical progress report for the SWC. Key activities for this reporting period include: (1) release of 2002 SWC request-for-proposal, (2) organized and hosted the Spring SWC meeting in Columbus, Ohio for membership proposal presentations and review; (3) tentatively scheduled the 2002 fall technology transfer meeting sites, and (4) continued to recruit additional Consortium members. In addition, a literature search that focuses on the use of lasers, microwaves, and acoustics for potential stripper well applications continued.
Date: August 27, 2002
Creator: Morrison, Joel L.
Object Type: Report
System: The UNT Digital Library
THE IMPLICIT HYBRID/PIC CODE ANTHEM. (open access)

THE IMPLICIT HYBRID/PIC CODE ANTHEM.

None
Date: August 27, 2002
Creator: MASON, RODNEY J
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 80, No. 274, Ed. 1 Tuesday, August 27, 2002 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 80, No. 274, Ed. 1 Tuesday, August 27, 2002

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: August 27, 2002
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Biosignatures of Pathogen and Host (open access)

Biosignatures of Pathogen and Host

In information theory, a signature is characterized by the information content as well as noise statistics of the communication channel. Biosignatures have analogous properties. A biosignature can be associated with a particular attribute of a pathogen or a host. However, the signature may be lost in backgrounds of similar or even identical signals from other sources. In this paper, we highlight statistical and signal processing challenges associated with identifying good biosignatures for pathogens in host and other environments. In some cases it may be possible to identify useful signatures of pathogens through indirect but amplified signals from the host. Discovery of these signatures requires new approaches to modeling and data interpretation. For environmental biosignal collections, it is possible to use signal processing techniques from other applications (e.g., synthetic aperture radar) to track the natural progression of microbes over large areas. We also present a computer-assisted approach to identify unique nucleic-acid based microbial signatures. Finally, an understanding of host-pathogen interactions will result in better detectors as well as opportunities in vaccines and therapeutics.
Date: August 27, 2002
Creator: Fitch, J. P.; Chromy, B. A.; Forde, C. E.; Garcia, E.; Gardner, S. N.; Gu, P. P. et al.
Object Type: Article
System: The UNT Digital Library
Homeland Security and the Davis-Bacon Act (open access)

Homeland Security and the Davis-Bacon Act

This report provides background information on the Davis-Bacon Act, and discusses the possible effect of section 194 on construction projects undertaken by agencies or related to programs transferred to the proposed Department of Homeland Security.
Date: August 27, 2002
Creator: Shimabukuro, Jon O.
Object Type: Report
System: The UNT Digital Library
Countries of the World and International Organizations: Sources of Information (open access)

Countries of the World and International Organizations: Sources of Information

This report provides a selection of materials for locating information on foreign countries and international organizations.
Date: August 27, 2002
Creator: Salazaar, Barbara A.
Object Type: Report
System: The UNT Digital Library
Simulation of Detonation Problems with the MLS Grid-Free Methodology (open access)

Simulation of Detonation Problems with the MLS Grid-Free Methodology

The Moving Least Squares (MLS) grid-free method, a simple, flexible finite difference method for solution of general continuum mechanics problems, especially detonation problems, is proposed in this paper. The spatial points that carry time dependent data are distributed in space in such a way that provides nearly uniform spacing of points, accurate presentation of boundaries, easy variation of resolution and arbitrary reorganization of the computational domain. Local finite difference operators are obtained with simple MLS differentiation. There is no specific topological or geometrical restriction of the distribution of data points. Therefore this method avoids many drawbacks of the traditional methods. Because of its flexibility, it can be used to simulate a wide range of mechanics problems. Because of its simplicity, it has the potential to become a preferred method. Most traditional computational continuum mechanics (CCM) methods, from a Smooth Particle Hydrodynamics (SPH) view, can be considered as special cases of grid-free methods of specific kernel functions. Such a generalization allows the development of a unified grid-free method that can represent most finite difference methods by switching the kernel functions. The flexible management and ease of coding make such a unified code attractive for many applications. A simple three-dimensional narrow-band level-set …
Date: August 27, 2002
Creator: Yao, J; Gunger, M E & Matuska, D A
Object Type: Article
System: The UNT Digital Library
Thermochemical Optimization of Float Glass Composition: Low-Alumina Glass Development (open access)

Thermochemical Optimization of Float Glass Composition: Low-Alumina Glass Development

Liquidus temperature (TL) was measured for a float-glass-type composition region with 72.7 to 74.0 mass% SiO2, 0.1 to 0.54 mass% Al2O3, 8.0 to 9.0 mass% CaO, 3.0 to 4.0 mass% MgO, and 13.1 to 14.2 mass% Na2O. Crystalline phases were identified at 900?C as cristobalite, wollastonite and devitrite. The primary phases were tridymite and wollastonite. Partial specific TLs were obtained from the data and compared with the literature.
Date: August 27, 2002
Creator: Hrma, Pavel R.; Smith, Donald E.; Yeager, John D. & Lam, Oanh P.
Object Type: Report
System: The UNT Digital Library
Altus Times (Altus, Okla.), Vol. 104, No. 140, Ed. 1 Tuesday, August 27, 2002 (open access)

Altus Times (Altus, Okla.), Vol. 104, No. 140, Ed. 1 Tuesday, August 27, 2002

Daily newspaper from Altus, Oklahoma that includes local, state, and national news along with advertising.
Date: August 27, 2002
Creator: Bush, Michael
Object Type: Newspaper
System: The Gateway to Oklahoma History
Imaging Catalytic Surfaces by Multiplexed Capillary Electrophoresis With Absorption Detection (open access)

Imaging Catalytic Surfaces by Multiplexed Capillary Electrophoresis With Absorption Detection

A new technique for in situ imaging and screening heterogeneous catalysts by using multiplexed capillary electrophoresis with absorption detection was developed. By bundling the inlets of a large number of capillaries, an imaging probe can be created that can be used to sample products formed directly from a catalytic surface with high spatial resolution. In this work, they used surfaces made of platinum, iron or gold wires as model catalytic surfaces for imaging. Various shapes were recorded including squares and triangles. Model catalytic surfaces consisting of both iron and platinum wires in the shape of a cross were also imaged successfully. Each of the two wires produced a different electrochemical product that was separated by capillary electrophoresis. Based on the collected data they were able to distinguish the products from each wire in the reconstructed image.
Date: August 27, 2002
Creator: Christodoulou, Michael
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 296, Ed. 1 Tuesday, August 27, 2002 (open access)

Sapulpa Daily Herald (Sapulpa, Okla.), Vol. 87, No. 296, Ed. 1 Tuesday, August 27, 2002

Daily newspaper from Sapulpa, Oklahoma that includes local, state, and national news along with advertising.
Date: August 27, 2002
Creator: Broaddus, Matthew B.
Object Type: Newspaper
System: The Gateway to Oklahoma History
Remote Field Eddy Current Probes for the Detection of Stress Corrosion in Transmission Pipelines (open access)

Remote Field Eddy Current Probes for the Detection of Stress Corrosion in Transmission Pipelines

Magnetic flux leakage (MFL) is a technique used widely in non-destructive testing (NDT) of natural gas and petroleum transmission pipelines. This inspection method relies on magnetizing the pipe-wall in axial direction. The MFL inspection tool is equipped with an array of Hall sensors located around the circumference of the pipe, which registers the flux leakage caused by any defects present in the pipe-wall. Currently, the tool magnetizes the pipewall in axial direction making it largely insensitive to axially oriented defects. One type of defect, which is of a growing concern in the gas and petroleum industry is the stress corrosion crack (SCC). The SCCs are a result of aging, corrosion, fatigue and thermal stresses. SCCs are predominantly axially oriented and are extremely tight, which makes them impossible to be detected using current inspection technology. A possible solution to this problem is to utilize the remote field eddy current (RFEC) effect to detect axially oriented defects. The RFEC method has been widely used in industry in the inspection of tubular products. The method uses a pair of excitation and pick-up coils. The pick-up coil located in the remote field region, usually two, three pipe-diameters away from the excitation coil. With RFEC …
Date: August 27, 2002
Creator: Ivanov, Plamen Alexandroz
Object Type: Thesis or Dissertation
System: The UNT Digital Library
Corrective Action Investigation Plan for Corrective Action Unit 127: Areas 25 and 26 Storage Tanks, Nevada Test Site, Nevada (Rev. No.: 0, August 2002) (open access)

Corrective Action Investigation Plan for Corrective Action Unit 127: Areas 25 and 26 Storage Tanks, Nevada Test Site, Nevada (Rev. No.: 0, August 2002)

This Corrective Action Investigation Plan (CAIP) contains the U.S. Department of Energy, National Nuclear Security Administration Nevada Operations Offices's approach to collect the data necessary to evaluate corrective action alternatives appropriate for the closure of Corrective Action Unit (CAU) 127 under the Federal Facility Agreement and Consent Order. Corrective Action Unit 127 is located on the Nevada Test Site approximately 65 miles northwest of Las Vegas, Nevada. This CAU is comprised of 12 Corrective Action Sites (CASs) located at Test Cell C; the Engine Maintenance, Assembly, and Disassembly (E-MAD) Facility; the X-Tunnel in Area 25; the Pluto Disassembly Facility; the Pluto Check Station; and the Port Gaston Training Facility in Area 26. These CASs include: CAS 25-01-05, Aboveground Storage Tank (AST); CAS 25-02-02, Underground Storage Tank (UST); CAS 25-23-11, Contaminated Materials; CAS 25-12-01, Boiler; CAS 25-01-06, AST; CAS 25-01-07, AST; CAS 25-02-13, UST; CAS 26- 01-01, Filter Tank (Rad) and Piping; CAS 26-01-02, Filter Tank (Rad); CAS 26-99-01, Radioactively Contaminated Filters; CAS 26-02-01, UST; CAS 26-23-01, Contaminated Liquids Spreader. Based on site history, process knowledge, and previous field efforts, contaminants of potential concern for CAU 127 include radionuclides, metals, total petroleum hydrocarbons, volatile organic compounds, asbestos, and polychlorinated biphenyls. Additionally, …
Date: August 27, 2002
Creator: United States. National Nuclear Security Administration. Nevada Operations Office.
Object Type: Report
System: The UNT Digital Library
Development of Novel Electrode Materials for the Electrocatalysis of Oxygen-Transfer and Hydrogen-Transfer Reactions (open access)

Development of Novel Electrode Materials for the Electrocatalysis of Oxygen-Transfer and Hydrogen-Transfer Reactions

Throughout this thesis, the fundamental aspects involved in the electrocatalysis of anodic O-transfer reactions and cathodic H-transfer reactions have been studied. The investigation into anodic O-transfer reactions at undoped and Fe(III)[doped MnO{sub 2} films] revealed that MnO{sub 2} film electrodes prepared by a cycling voltammetry deposition show improved response for DMSO oxidation at the film electrodes vs. the Au substrate. Doping of the MnO{sub 2} films with Fe(III) further enhanced electrode activity. Reasons for this increase are believed to involve the adsorption of DMSO by the Fe(III) sites. The investigation into anodic O-transfer reactions at undoped and Fe(III)-doped RuO{sub 2} films showed that the Fe(III)-doped RuO{sub 2}-film electrodes are applicable for anodic detection of sulfur compounds. The Fe(III) sites in the Fe-RuO{sub 2} films are speculated to act as adsorption sites for the sulfur species while the Ru(IV) sites function for anodic discharge of H{sub 2}O to generate the adsorbed OH species. The investigation into cathodic H-transfer reactions, specifically nitrate reduction, at various pure metals and their alloys demonstrated that the incorporation of metals into alloy materials can create a material that exhibits bifunctional properties for the various steps involved in the overall nitrate reduction reaction. The Sb{sub 10}Sn{sub 20}Ti{sub …
Date: August 27, 2002
Creator: Simpson, Brett Kimball
Object Type: Thesis or Dissertation
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, August 27, 2002 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Tuesday, August 27, 2002

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: August 27, 2002
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Appropriations for FY2003: U.S. Department of Agriculture and Related Agencies (open access)

Appropriations for FY2003: U.S. Department of Agriculture and Related Agencies

Appropriations are one part of a complex federal budget process that includes budget resolutions, appropriations (regular, supplemental, and continuing) bills, rescissions, and budget reconciliation bills. This report is a guide to one of the 13 regular appropriations bills that Congress considers each year. It is designed to supplement the information provided by the House and Senate Appropriations Subcommittees on Agriculture.
Date: August 27, 2002
Creator: Chite, Ralph M.
Object Type: Report
System: The UNT Digital Library