Epigenetic reversion of breast carcinoma phenotype is accompanied by DNA sequestration (open access)

Epigenetic reversion of breast carcinoma phenotype is accompanied by DNA sequestration

The importance of microenvironment and context in regulation of tissue-specific genes is finally well established. DNA exposure to, or sequestration from, nucleases can be used to detect differences in higher order chromatin structure in intact cells without disturbing cellular or tissue architecture. To investigate the relationship between chromatin organization and tumor phenotype, we utilized an established 3-D assay where normal and malignant human breast cells can be easily distinguished by the morphology of the structures they make (acinus-like vs tumor-like, respectively). We show that these phenotypes can be distinguished also by sensitivity to AluI digestion where the malignant cells are resistant to digestion relative to non-malignant cells. Reversion of the T4-2 breast cancer cells by either cAMP analogs, or a phospatidylinositol 3-kinase (P13K) inhibitor not only reverted the phenotype, but also the chromatin sensitivity to AluI. By using different cAMP-analogs, we show that the cAMP-induced phenotypic reversion, polarization, and shift in DNA organization act through a cAMP-dependent-protein-kinase A-coupled signaling pathway. Importantly, inhibitory antibody to fibronectin also reverted the malignant phenotype, polarized the acini, and changed chromatin sequestration. These experiments show not only that modifying the tumor microenvironment can alter the organization of tumor cells but also that architecture of the …
Date: July 19, 2006
Creator: Sandal, Tone; Valyi-Nagy, Klara; Spencer, Virginia A.; Folberg,Robert; Bissell, Mina J. & Maniotis, Andrew J.
Object Type: Article
System: The UNT Digital Library
History and Evolution of Control Banding: A Review (open access)

History and Evolution of Control Banding: A Review

Control Banding (CB) strategies offer simplified solutions for controlling worker exposures to constituents often encountered in the workplace. The original CB model was developed within the pharmaceutical industry; however, the modern movement involves models developed for non-experts to input hazard and exposure potential information for bulk chemical processes, receiving control advice as a result. The CB approach utilizes these models for the dissemination of qualitative and semi-quantitative risk assessment tools being developed to complement the traditional industrial hygiene model of air sampling and analysis. It is being applied and tested in small and medium size enterprises (SMEs) within developed countries and industrially developing countries; however, large enterprises (LEs) have also incorporated these strategies within chemical safety programs. Existing research of the components of the most available CB model, the Control of Substances Hazardous to Health (COSHH) Essentials, has shown that exposure bands do not always provide adequate margins of safety, that there is a high rate of under-control errors, that it works better with dusts than with vapors, that there is an inherent inaccuracy in estimating variability, and that when taken together the outcomes of this model may lead to potentially inappropriate workplace confidence in chemical exposure reduction in some …
Date: July 19, 2006
Creator: Zalk, D. & Nelson, D.
Object Type: Article
System: The UNT Digital Library
On-Line Coolant Chemistry Analysis (open access)

On-Line Coolant Chemistry Analysis

Impurities in the gas coolant of the space nuclear power plant (SNPP) can provide valuable indications of problems in the reactor and an overall view of system health. By monitoring the types and amounts of these impurities, much can be implied regarding the status of the reactor plant. However, a preliminary understanding of the expected impurities is important before evaluating prospective detection and monitoring systems. Currently, a spectroscopy system is judged to hold the greatest promise for monitoring the impurities of interest in the coolant because it minimizes the number of entry and exit points to the plant and provides the ability to detect impurities down to the 1 ppm level.
Date: July 19, 2006
Creator: Bachman, LM
Object Type: Report
System: The UNT Digital Library
Simple Common Plane contact detection algorithm for FE/FD methods (open access)

Simple Common Plane contact detection algorithm for FE/FD methods

Common-plane (CP) algorithm is widely used in Discrete Element Method (DEM) to model contact forces between interacting particles or blocks. A new simple contact detection algorithm is proposed to model contacts in FE/FD methods which is similar to the CP algorithm. The CP is defined as a plane separating interacting faces of FE/FD mesh instead of blocks or particles in the original CP method. The method does not require iterations. It is very robust and easy to implement both in 2D and 3D case.
Date: July 19, 2006
Creator: Vorobiev, O
Object Type: Article
System: The UNT Digital Library
Study of the Electron Beam Dynamics in the Fermi @ Elettra Linac (open access)

Study of the Electron Beam Dynamics in the Fermi @ Elettra Linac

A study of the electron beam dynamics in the linac is conducted for the FERMI free electron laser (FEL) founded for construction at the Sincrotrone Trieste.
Date: July 19, 2006
Creator: Cornacchia, M.; Craievich, P.; Di Mitri, S.; Pogorelov, I.; Qiang, J.; Venturini, M. et al.
Object Type: Article
System: The UNT Digital Library
Characterization of the PEP-II Colliding-Beam Phase Space by the Boost Method (open access)

Characterization of the PEP-II Colliding-Beam Phase Space by the Boost Method

We present a novel approach to characterize the colliding-beam phase space at the interaction point of the energy-asymmetric PEP-II B-Factory. The method exploits the fact that the transverse-boost distribution of e{sup +}e{sup -} {yields} {mu}{sup +}{mu}{sup -} events reconstructed in the BABAR detector reflects that of the colliding electrons and positrons. The mean boost direction, when combined with the measured orientation of the luminous ellipsoid, determines the e{sup +}-e{sup -} crossing angles. The average angular spread of the transverse boost vector provides an accurate measure of the angular divergence of the incoming high-energy beam, confirming the presence of a sizeable dynamic-{beta} effect. The longitudinal and transverse dependence of the boost angular spread also allow to extract from the continuously-monitored distributions detailed information about the emittances and IP {beta}-functions of both beams during high-luminosity operation.
Date: July 19, 2006
Creator: Weaver, M.; Kozanecki, W. & Viaud, B.
Object Type: Article
System: The UNT Digital Library
NUCLEAR NON-PROLIFERATION-TASK 1: Deployable Plume and Aerosol Release Prediction and Tracking System (open access)

NUCLEAR NON-PROLIFERATION-TASK 1: Deployable Plume and Aerosol Release Prediction and Tracking System

This contract was awarded in response to a proposal in which a deployable plume and aerosol release prediction and tracking system would be designed, fabricated, and tested. The system would gather real time atmospheric data and input it into a real time atmospheric model that could be used for plume predition and tracking. The system would be able to be quickly deployed by aircraft to points of interest or positioned for deployment by vehicles. The system would provide three dimensional (u, v, and w) wind vector data, inversion height measurements, surface wind information, classical weather station data, and solar radiation. The on-board real time computer model would provide the prediction of the behavior of plumes and released aerosols.
Date: July 19, 2006
Creator: John Kleppe, Ph.D., William Norris, Ph.D., Mehdi Etezada, Ph.D., P.E.
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia

This is the third quarter progress report of Phase II of a three-phase project to develop and evaluate the efficacy of developing multiple environmental market trading credits on a partially reclaimed surface mined site near Valley Point, Preston County, WV. Construction of the passive acid mine drainage (AMD) treatment system was completed but several modifications from the original design had to be made following the land survey and during construction to compensate for unforeseen circumstances. We continued to collect baseline quality data from the Conner Run AMD seeps to confirm the conceptual and final design for the passive AMD treatment system.
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia

None
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia

None
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia

None
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library
An Experimental Investigation of Detonation Corner-Turning Using High Resolution Radiography (open access)

An Experimental Investigation of Detonation Corner-Turning Using High Resolution Radiography

We have performed experiments investigating detonation corner turning over a range of high-explosives including LX-17, Composition B, LX-04 and Tritonal. The primary diagnostic utilized here was a new high-resolution x-ray system that was capable of recording a time sequence of the detonation process as it negotiated the corner of interest and propagated. For LX-17 our data detail the formation of a significant dead-zone. Although the detonation eventually turned the corner in LX-17, the dead zone persisted to late times and evidence exists that it never was consumed by either detonation or fast combustion processes. In LX-17 the detonations ability to corner-turn increases as the density is reduced. Furthermore, lowering the density decreases the size of the dead-zone and alters its shape. The other high-explosives investigated were able to turn the corner immediately with no indication of any dead-zone formation.
Date: July 19, 2006
Creator: Molitoris, J D; Andreski, H G; Garza, R G; Batteux, J D & Souers, P C
Object Type: Article
System: The UNT Digital Library
Gas production potential of disperse low-saturation hydrateaccumulations in oceanic sediments (open access)

Gas production potential of disperse low-saturation hydrateaccumulations in oceanic sediments

In this paper we evaluate the gas production potential ofdisperse, low-saturation (SH<0.1) hydrate accumulations in oceanicsediments. Such hydrate-bearing sediments constitute a significantportion of the global hydrate inventory. Using numerical simulation, weestimate (a) the rates of gas production and gas release from hydratedissociation, (b) the corresponding cumulative volumes of released andproduced gas, as well as (c) the water production rate and the mass ofproduced water from disperse, low-SH hydrate-bearing sediments subject todepressurization-induced dissociation over a 10-year production period.We investigate the sensitivity of items (a) to (c) to the followinghydraulic properties, reservoir conditions, and operational parameters:intrinsic permeability, porosity, pressure, temperature, hydratesaturation, and constant pressure at which the production well is kept.The results of this study indicate that, despite wide variations in theaforementioned parameters (covering the entire spectrum of suchdeposits), gas production is very limited, never exceeding a few thousandcubic meters of gas during the 10-year production period. Such lowproduction volumes are orders of magnitude below commonly acceptedstandards of economic viability, and are further burdened with veryunfavorable gas-to-water ratios. The unequivocal conclusion from thisstudy is that disperse, low-SH hydrate accumulations in oceanic sedimentsare not promising targets for gas production by means ofdepressurization-induced dissociation, and resources for early hydrateexploitation should be focused elsewhere.
Date: July 19, 2006
Creator: Moridis, George J. & Sloan, E. Dendy
Object Type: Article
System: The UNT Digital Library
2005 Annual Operations Report for INTEC Operable Unit 3-13, Group 1, Tank Farm Interim Action (open access)

2005 Annual Operations Report for INTEC Operable Unit 3-13, Group 1, Tank Farm Interim Action

This annual operations report describes the requirements followed and activities conducted to inspect, monitor, and maintain the items installed during performance of the Waste Area Group 3, Operable Unit 3-13, Group 1, Tank Farm Interim Action, at the Idaho Nuclear Technology and Engineering Center. This report describes inspection and monitoring activities fro the surface-sealed areas within the tank farm, concrete-lined ditches and culverts in and around the tank farm, the lift station, and the lined evaporation pond. These activities are intended to assure that the interim action is functioning adequately to meet the objectives stated in the Operable Unit 3-13, Record of Decision for the Group 1, Tank Farm Interim Action, (DOE/ID-10660) and as amended by the agreement to resolve dispute, which was effective in February 2003.
Date: July 19, 2006
Creator: Shanklin, D.
Object Type: Report
System: The UNT Digital Library
Fermi Timing and Synchronization System (open access)

Fermi Timing and Synchronization System

The Fermi FEL will depend critically on precise timing of its RF, laser and diagnostic subsystems. The timing subsystem to coordinate these functions will need to reliably maintain sub-100fs synchronicity between distant points up to 300m apart in the Fermi facility. The technology to do this is not commercially available, and has not been experimentally demonstrated in a working facility. Therefore, new technology must be developed to meet these needs. Two approaches have been researched by different groups working with the Fermi staff. At MIT, a pulse transmission scheme has been developed for synchronization of RF and laser devices. And at LBL, a CW transmission scheme has been developed for RF and laser synchronization. These respective schemes have advantages and disadvantages that will become better understood in coming years. This document presents the work done by both teams, and suggests a possible system design which integrates them both. The integrated system design provides an example of how choices can be made between the different approaches without significantly changing the basic infrastructure of the system. Overall system issues common to any synchronization scheme are also discussed.
Date: July 19, 2006
Creator: Wilcox, R.; Staples, J.; Doolittle, L.; Byrd, J.; Ratti, A.; Kaertner, F. X. et al.
Object Type: Report
System: The UNT Digital Library
Hot Leg Piping Materials Issues (open access)

Hot Leg Piping Materials Issues

With Naval Reactors (NR) approval of the Naval Reactors Prime Contractor Team (NRPCT) recommendation to develop a gas cooled reactor directly coupled to a Brayton power conversion system as the space nuclear power plant (SNPP) for Project Prometheus (References a and b) the reactor outlet piping was recognized to require a design that utilizes internal insulation (Reference c). The initial pipe design suggested ceramic fiber blanket as the insulation material based on requirements associated with service temperature capability within the expected range, very low thermal conductivity, and low density. Nevertheless, it was not considered to be well suited for internal insulation use because its very high surface area and proclivity for holding adsorbed gases, especially water, would make outgassing a source of contaminant gases in the He-Xe working fluid. Additionally, ceramic fiber blanket insulating materials become very friable after relatively short service periods at working temperatures and small pieces of fiber could be dislodged and contaminate the system. Consequently, alternative insulation materials were sought that would have comparable thermal properties and density but superior structural integrity and greatly reduced outgassing. This letter provides technical information regarding insulation and materials issues for the Hot Leg Piping preconceptual design developed for the …
Date: July 19, 2006
Creator: Munne, V.
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virgina (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virgina

None
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia

None
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia

None
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library
A Perfect Electrode to Suppress Secondary Electrons inside the Magnets (open access)

A Perfect Electrode to Suppress Secondary Electrons inside the Magnets

An electron cloud due to multipacting in the positron ring of B-factories and the damping ring of the International Linear Collider (ILC) is one of the main concerns. The electron cloud in the drift region can be suppressed by a solenoid. However, the solenoid doesn't work inside a magnet. Numerical studies show that there is strong multipacting in a dipole magnet of a B-factory positron ring. Electrons also can be trapped inside quadrupole and sextupole magnets. The electron cloud from dipole magnets and wigglers in the positron damping ring of the ILC gives a critical limitation on the choice of a circumference of the damping ring, which directly results in a choice of two 6 km rings as the baseline for the positron damping ring. Various electrodes have been studied using the program CLOUDLAND. Our studies show that a wire type of the electrode with a few hundred voltages works perfectly to kill the secondary electrons inside various magnets.
Date: July 19, 2006
Creator: Wang, L.; Fukuma, H.; Kurokawa, S.; Pivi, M. & Xia, G.
Object Type: Article
System: The UNT Digital Library
Carbon-Carbon Composites as Recuperator Material for Direct Gas Brayton Systems (open access)

Carbon-Carbon Composites as Recuperator Material for Direct Gas Brayton Systems

Of the numerous energy conversion options available for a space nuclear power plant (SNPP), one that shows promise in attaining reliable operation and high efficiency is the direct gas Brayton (GB) system. In order to increase efficiency, the GB system incorporates a recuperator that accounts for nearly half the weight of the energy conversion system (ECS). Therefore, development of a recuperator that is lighter and provides better performance than current heat exchangers could prove to be advantageous. The feasibility of a carbon-carbon (C/C) composite recuperator core has been assessed and a mass savings of 60% and volume penalty of 20% were projected. The excellent thermal properties, high-temperature capabilities, and low density of carbon-carbon materials make them attractive in the GB system, but development issues such as material compatibility with other structural materials in the system, such as refractory metals and superalloys, permeability, corrosion, joining, and fabrication must be addressed.
Date: July 19, 2006
Creator: Wolf, RA
Object Type: Report
System: The UNT Digital Library
Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia (open access)

Demonstrating a Market-Based Approach to the Reclamation of Mined Lands in West Virginia

None
Date: July 19, 2006
Creator: Goodrich-Mahoney, John W. & Ziemkiewicz, Paul
Object Type: Report
System: The UNT Digital Library