Language

8-oxoguainine enhances bending of DNA that favors binding of glycosylases (open access)

8-oxoguainine enhances bending of DNA that favors binding of glycosylases

Molecular dynamics (MD) simulations were carried out on the DNA oligonucleotide GGGAACAACTAG:CTAGTTGTTCCC in its native form and with guanine in the central G19:C6 base pair replaced by 8-oxoguanine (8oxoG). A box of explicit water molecules was used for solvation and Na+ counterions were added to neutralize the system. The direction and magnitude of global bending were assessed by a technique used previously to analyze simulations of DNA containing a thymine dimer. The presence of 8oxoG did not greatly affect the magnitude of DNA bending; however, bending into the major groove was significantly more probable when 8oxoG replaced G19. Crystal structures of glycosylases bound to damaged-DNA substrates consistently show a sharp bend into the major groove at the damage site. We conclude that changes in bending dynamics that assist the formation of this kink are a part of the mechanism by which glycosylases of the base excision repair pathway recognize the presence of 8oxoG in DNA.
Date: April 23, 2003
Creator: Miller, John H.
Object Type: Article
System: The UNT Digital Library
The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, April 23, 2003 (open access)

The Alvin Advertiser (Alvin, Tex.), Ed. 1 Wednesday, April 23, 2003

Weekly newspaper from Alvin, Texas that includes local, state, and national news along with advertising.
Date: April 23, 2003
Creator: Schwind, Jim & Holton, Kathleen
Object Type: Newspaper
System: The Portal to Texas History
The Americans with Disabilities Act (ADA): Statutory Language and Recent Issues (open access)

The Americans with Disabilities Act (ADA): Statutory Language and Recent Issues

This report discusses the major provisions of the ADA and will discuss selected recent issues, including the supreme court cases. It will be updated as development warrant.
Date: April 23, 2003
Creator: Jones, Nancy Lee
Object Type: Report
System: The UNT Digital Library
The Americans with Disabilities Act (ADA): Statutory Language and Recent Issues (open access)

The Americans with Disabilities Act (ADA): Statutory Language and Recent Issues

This report summarizes the major provisions of the Americans with Disabilities Act (ADA), and also discusses selected recent issues, including ten ADA Supreme Court cases.
Date: April 23, 2003
Creator: Jones, Nancy Lee
Object Type: Report
System: The UNT Digital Library
Analysis of Barrel Support Saddles and Forces Between Modules During Assembly. (open access)

Analysis of Barrel Support Saddles and Forces Between Modules During Assembly.

As the Barrel Tile Calorimeter is constructed, the support saddles and the modules will be subjected to different forces, stresses, and deflections than when completely assembled. The purpose of this analysis is to examine the forces, stresses, and deflections acting on the support saddles and modules at various stages of assembly. The nominal weight of a barrel module is 20 tons. CERN Document number ATL-LB-EA-0001 'Summary of the Structural Analysis of the Barrel Support Saddles' describes in detail the structural analysis of the saddles and the completed barrel assembly. These calculations followed Eurocode 3. This paper examined several load cases which occur during the assembly of the Barrel. The following are the main conclusions: (1) The assembly is not stable until 18 modules are in place, and only then can the support cradle be removed; (2) The forces between modules are nominal and are far less that the forces in the completed cylinder with 64 modules in place and the cryostat load applied; (3) All of the stresses in the connections between modules are within acceptable limits; and (4) The interface between the cryostat supports and the cryostat move approximately 1.0 mm in the X and Y directions when the …
Date: April 23, 2003
Creator: Guarino, V. J.
Object Type: Report
System: The UNT Digital Library
Aqueous corrosion of aluminum-based nuclear fuel. (open access)

Aqueous corrosion of aluminum-based nuclear fuel.

As part of the U.S. National Spent Nuclear Fuel Program, aluminide fuels (UAl{sub x}) are being tested under conditions that might exist in the proposed repository at Yucca Mountain, Nevada. Intermittent drip tests at 90 C were completed for up to 183 days on partially declad, unirradiated, low-enriched UAl{sub x} samples. Through 183 days of exposure to modified water from the J-13 well at 90 C, the fuel coupon remained in good mechanical condition. Only a tarnishing of the surface was observed and no spalled products were found in the fuel holder. The mechanism for alteration is consistent with that observed from dry oxidation experiments on UAl{sub x} (for the initial corrosion) and humid UO{sub 2} oxidation (for the subsequent paragenesis). Specifically, solid-state conversion of UAl{sub x} into UO{sub 2} and oxidized Al is followed by further oxidation, dissolution of the uranium, and reprecipitation as uranyl oxyhydroxides. The release rate of uranium varied from 0.23 to 2.9 mg/m{sup 2}/day (avg. = 0.97 mg U/m{sup 2}/day) depending on the specimen and test interval, but was similar in magnitude to that observed in earlier flow-through and drip tests with irradiated UAl{sub x} and UO{sub 2}. Most (mean=87%) of the released uranium sorbed …
Date: April 23, 2003
Creator: Kaminski, M.
Object Type: Report
System: The UNT Digital Library
The Archer Advocate (Holliday, Tex.), Vol. 1, No. 3, Ed. 1 Wednesday, April 23, 2003 (open access)

The Archer Advocate (Holliday, Tex.), Vol. 1, No. 3, Ed. 1 Wednesday, April 23, 2003

Weekly newspaper from Holliday, Texas that includes local, state, and national news along with advertising.
Date: April 23, 2003
Creator: Thomas, John
Object Type: Newspaper
System: The Portal to Texas History
Astronomy Applications of Adaptive Optics at Lawrence Livermore National Laboratory (open access)

Astronomy Applications of Adaptive Optics at Lawrence Livermore National Laboratory

Astronomical applications of adaptive optics at Lawrence Livermore National Laboratory (LLNL) has a history that extends from 1984. The program started with the Lick Observatory Adaptive Optics system and has progressed through the years to lever-larger telescopes: Keck, and now the proposed CELT (California Extremely Large Telescope) 30m telescope. LLNL AO continues to be at the forefront of AO development and science.
Date: April 23, 2003
Creator: Bauman, B J & Gavel, D T
Object Type: Article
System: The UNT Digital Library
The Baytown Sun (Baytown, Tex.), Vol. 81, No. 149, Ed. 1 Wednesday, April 23, 2003 (open access)

The Baytown Sun (Baytown, Tex.), Vol. 81, No. 149, Ed. 1 Wednesday, April 23, 2003

Daily newspaper from Baytown, Texas that includes local, state, and national news along with advertising.
Date: April 23, 2003
Creator: Cash, Wanda Garner
Object Type: Newspaper
System: The Portal to Texas History
Cherokeean/Herald (Rusk, Tex.), Vol. 154, No. 9, Ed. 1 Wednesday, April 23, 2003 (open access)

Cherokeean/Herald (Rusk, Tex.), Vol. 154, No. 9, Ed. 1 Wednesday, April 23, 2003

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: April 23, 2003
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History
The Clifton Record (Clifton, Tex.), Vol. 108, No. 33, Ed. 1 Wednesday, April 23, 2003 (open access)

The Clifton Record (Clifton, Tex.), Vol. 108, No. 33, Ed. 1 Wednesday, April 23, 2003

Semi-weekly newspaper from Clifton, Texas that includes local, state, and national news along with advertising.
Date: April 23, 2003
Creator: Smith, W. Leon
Object Type: Newspaper
System: The Portal to Texas History
The Collegian (Hurst, Tex.), Vol. 15, No. 23, Ed. 1 Wednesday, April 23, 2003 (open access)

The Collegian (Hurst, Tex.), Vol. 15, No. 23, Ed. 1 Wednesday, April 23, 2003

Weekly student newspaper published in Hurst, Texas and serving the Tarrant County College District that includes school news and information along with advertising.
Date: April 23, 2003
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Colony Courier-Leader (The Colony, Tex.), Vol. 22, No. 11, Ed. 1 Wednesday, April 23, 2003 (open access)

The Colony Courier-Leader (The Colony, Tex.), Vol. 22, No. 11, Ed. 1 Wednesday, April 23, 2003

Weekly newspaper from The Colony, Texas that includes local, state, and national news along with advertising.
Date: April 23, 2003
Creator: Shafer, Leah
Object Type: Newspaper
System: The Portal to Texas History
Combustion of Shock-Dispersed Fuels in a Chamber (open access)

Combustion of Shock-Dispersed Fuels in a Chamber

In previous studies we have investigated after-burning effects of a fuel-rich explosive (TNT). In that case the detonation only releases about 30 % of the available energy, but generates a hot cloud of fuel that can burn in the ambient air, thus evoking an additional energy release that is distributed in space and time. The current series of small-scale experiments can be looked upon as a natural generalization of this mechanism: a booster charge disperses a (non-explosive) fuel, provides mixing with air and - by means of the hot detonation products - energy to ignite the fuel. The current version of our miniature Shock-Dispersed-Fuel (SDF) charges consists of a spherical booster charge of 0.5 g PETN, embedded in a paper cylinder of approximately 2.2 cm3, which is filled with powdered fuel compositions. The main compositions studied up to now contain aluminum powder, hydrocarbon powders like polyethylene or sucrose and/or carbon particles. These charges were studied in three different chambers of 4-1, 6.6-1 and 40.5-1 volume. In general, the booster charge was sufficient to initiate burning of the fuel. This modifies the pressure signatures measured with a number of wall gages and increases the quasi-static overpressure level obtained in the chambers. …
Date: April 23, 2003
Creator: Neuwald, P; Reichenbach, H & Kuhl, A L
Object Type: Article
System: The UNT Digital Library
Critical Infrastructure: Control Systems and the Terrorist Threat (open access)

Critical Infrastructure: Control Systems and the Terrorist Threat

This report addresses the cyber-vulnerability of critical infrastructure industries which regularly use industrial control systems. Industrial control systems may be vulnerable to infiltration by different routes, including wireless transmission, direct access to control system computers, exploitation of dial-up modems used for maintenance, or through the Internet. This report will specifically discuss the potential for access to industrial control systems through the Internet.
Date: April 23, 2003
Creator: Shea, Dana A.
Object Type: Report
System: The UNT Digital Library
Development of Brazing Technology for Use in High- Temperature Gas Separation Equipment (open access)

Development of Brazing Technology for Use in High- Temperature Gas Separation Equipment

The development of high-temperature electrochemical devices such as oxygen and hydrogen separators, fuel gas reformers, solid oxide fuel cells, and chemical sensors is part of a rapidly expanding segment of the solid state technology market. These devices employ an ionic conducting ceramic as the active membrane that establishes the electrochemical potential of the device, either under voltage (i.e. to carry out gas separation) or under chemical gradient (to develop an electrical potential and thereby generate electrical power). Because the device operates under an ionic gradient that develops across the electrolyte, hermiticity across this layer is paramount. That is, not only must this thin ceramic membrane be dense with no interconnected porosity, but it must be connected to the rest of the device, typically constructed from a heat resistant alloy, with a high-temperature, gas-tight seal. A significant engineering challenge in fabricating these devices is how to effectively join the thin electrochemically active membrane to the metallic body of the device such that the resulting seal is hermetic, rugged, and stable during continuous high temperature operation. Active metal brazing is the typical method of joining ceramic and metal engineering components. It employs a braze alloy that contains one or more reactive elements, …
Date: April 23, 2003
Creator: Weil, K. S.; Hardy, J. S. & Kim, J. Y.
Object Type: Article
System: The UNT Digital Library
Development of Inorganic Membranes for Hydrogen Separation (open access)

Development of Inorganic Membranes for Hydrogen Separation

This paper presents information and data relative to recent advances in the development at Oak Ridge National Laboratory of porous inorganic membranes for high-temperature hydrogen separation. The Inorganic Membrane Technology Laboratory, which was formerly an organizational element of Bechtel Jacobs Company, LLC, was formally transferred to Oak Ridge National Laboratory on August 1, 2002, as a result of agreements reached between Bechtel Jacobs Company, the management and integration contractor at the East Tennessee Technology Park (formerly the Oak Ridge Gaseous Diffusion Plant or Oak Ridge K-25 Site); UT-Battelle, the management and operating contractor of Oak Ridge National Laboratory; and the U.S. Department of Energy (DOE) Oak Ridge Operations Office. Research emphasis during the last year has been directed toward the development of high-permeance (high-flux) and high-separation-factor metal-supported membranes. Performance data for these membranes are presented and are compared with performance data for membranes previously produced under this program and for membranes produced by other researchers. New insights into diffusion mechanisms are included in the discussion. Fifteen products, many of which are the results of research sponsored by the DOE Fossil Energy Advanced Research Materials Program, have been declared unclassified and have been approved for commercial production.
Date: April 23, 2003
Creator: Bischoff, Brian L. & Judkins, Roddie R.
Object Type: Article
System: The UNT Digital Library
DEVELOPMENT OF METALLIC HOT GAS FILTERS (open access)

DEVELOPMENT OF METALLIC HOT GAS FILTERS

Successful development of metallic filters with high temperature oxidation/corrosion resistance for fly ash capture is a key to enabling advanced coal combustion and power generation technologies. Compared to ceramic filters, metallic filters can offer increased resistance to impact and thermal fatigue, greatly improving filter reliability. A beneficial metallic filter structure, composed of a thin-wall (0.5mm) tube with uniform porosity (about 30%), is being developed using a unique spherical powder processing and partial sintering approach, combined with porous sheet rolling and resistance welding. Alloy choices based on modified superalloys, e.g., Ni-16Cr-4.5Al-3Fe (wt.%), are being tested in porous and bulk samples for oxide (typically alumina) scale stability in simulated oxidizing/sulfidizing atmospheres found in PFBC and IGCC systems at temperatures up to 850 C. Recent ''hanging o-ring'' exposure tests in actual combustion systems at a collaborating DOE site (EERC) have been initiated to study the combined corrosive effects from particulate deposits and hot exhaust gases. New studies are exploring the correlation between sintered microstructure, tensile strength, and permeability of porous sheet samples.
Date: April 23, 2003
Creator: Anderson, I. E.; Gleeson, B. & Terpstra, R. L.
Object Type: Article
System: The UNT Digital Library
Distribution System of the Future (open access)

Distribution System of the Future

The distribution system of the future is going to be as much of a revolution to the electric energy industry as the wireless telephone has been to consumer communications. An electricity market transformation must occur before the changes can take place, but this evolution is already starting to occur in many parts of the country. In this paper, we discuss a vision for a future distribution system, areas that will be key for technology development, and the advantages of the new electricity market. Present day distribution systems are in a sense, unintelligent. Distribution systems respond to faults, or short circuits, by sensing the very high fault current and then opening circuit breakers to isolate the fault. Some newer automated systems determine fault location and then close other circuit breakers to provide an alternate path for power after the fault so that the number of customers left without power is minimized, but the extent of the reconfiguration is limited. Distribution systems also have some methods to regulate voltage, but there is little real time local response to contingencies such as loss of a transmission line or a generator. In present day distribution systems, there is very little control of load, or …
Date: April 23, 2003
Creator: Kueck, JD
Object Type: Report
System: The UNT Digital Library
Energy Policy: The Continuing Debate (open access)

Energy Policy: The Continuing Debate

On April 11, 2003, the House passed comprehensive energy legislation, H.R. 6 (247-175).Action on comprehensive energy legislation is in progress in the Senate. The Senate Energy and Natural Resources Committee began markup of a comprehensive energy bill on April 7, 2003, agreeing by week’s end to provisions regarding hydrogen, hydroelectric relicensing, nuclear and renewable energy. On April 11, 2003, Chairman Domenici pulled a controversial section on climate change from the bill and indicated it would be addressed later.
Date: April 23, 2003
Creator: Bamberger, Robert L.
Object Type: Report
System: The UNT Digital Library
Environmental Assessment of Ground Water Compliance at the Naturita, Colorado, UMTRA Project Site (open access)

Environmental Assessment of Ground Water Compliance at the Naturita, Colorado, UMTRA Project Site

This Environmental Assessment addresses the environmental effects of a proposed action and the no action alternative to comply with U.S. Environmental Protection Agency (EPA) ground water standards at the Naturita, Colorado, Uranium Mill Tailings Remedial Action Project site. In 1998, the U.S. Department of Energy (DOE) completed surface cleanup at the site and encapsulated the tailings in a disposal cell 15 miles northwest near the former town of Uravan, Colorado. Ground water contaminants of potential concern at the Naturita site are uranium and vanadium. Uranium concentrations exceed the maximum concentration limit (MCL) of 0.044 milligram per liter (mg/L). Vanadium has no MCL; however, vanadium concentrations exceed the EPA Region III residential risk-based concentration of 0.33 mg/L (EPA 2002). The proposed compliance strategy for uranium and vanadium at the Naturita site is no further remediation in conjunction with the application of alternate concentration limits. Institutional controls with ground water and surface water monitoring will be implemented for these constituents as part of the compliance strategy. This compliance strategy will be protective of human health and the environment. The proposed monitoring program will begin upon regulatory concurrence with the Ground Water Compliance Action Plan (DOE 2002a). Monitoring will consist of verifying that …
Date: April 23, 2003
Creator: unknown
Object Type: Report
System: The UNT Digital Library
Estate Tax Legislation in the 108th Congress (open access)

Estate Tax Legislation in the 108th Congress

Under provisions of the Economic Growth and Tax Relief Reconciliation Act of 2001 (EGTRRA, P.L. 107-16, enacted June 7, 2001), the estate tax is scheduled to be repealed in 2010 but reinstated in 2011. All tax cut provisions of EGTRRA are scheduled to sunset on December 31, 2010. This report tracks actions in the 108th Congress to permanently repeal the estate tax or to retain but alter the tax.
Date: April 23, 2003
Creator: Noto, Nonna A.
Object Type: Report
System: The UNT Digital Library
The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, April 23, 2003 (open access)

The Express-Star (Chickasha, Okla.), Ed. 1 Wednesday, April 23, 2003

Daily newspaper from Chickasha, Oklahoma that includes local, state, and national news along with advertising.
Date: April 23, 2003
Creator: Bush, Kent
Object Type: Newspaper
System: The Gateway to Oklahoma History
Federal Pensions: DOL Oversight and Thrift Savings Plan Accountability (open access)

Federal Pensions: DOL Oversight and Thrift Savings Plan Accountability

A letter report issued by the General Accounting Office with an abstract that begins "The Thrift Savings Plan (TSP) is a retirement savings and investment plan for federal employees, governed by the Federal Retirement Thrift Investment Board (the TSP Board). Recent events relating to the TSP Board's contract to upgrade TSP's record keeping system have raised questions about the management of the TSP. In light of the TSP Board's actions relating to the record keeping system and the recent submission of the TSP Board's legislative proposal that would enhance its independence, Congressional requesters asked us to examine federal oversight of the TSP Board. Specifically, our objectives were to (1) describe the Department of Labor's (DOL) oversight authority, under the Federal Employees' Retirement System Act of 1986 (FERSA) and (2) determine the actions DOL has taken in exercising its authority over TSP."
Date: April 23, 2003
Creator: United States. General Accounting Office.
Object Type: Report
System: The UNT Digital Library