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Information Quality Act: Expanded Oversight and Clearer Guidance by the Office of Management and Budget Could Improve Agencies' Implementation of the Act (open access)

Information Quality Act: Expanded Oversight and Clearer Guidance by the Office of Management and Budget Could Improve Agencies' Implementation of the Act

A letter report issued by the Government Accountability Office with an abstract that begins "The importance and widespread use of federal information makes its accuracy imperative. The Information Quality Act (IQA) required that the Office of Management and Budget (OMB) issue guidelines to ensure the quality of information disseminated by federal agencies by fiscal year 2003. GAO was asked to (1) assess OMB's role in helping agencies implement IQA; (2) identify the number, type, and source of IQA correction requests agencies received; and (3) examine if IQA has adversely affected agencies' overall operations and, in particular, rulemaking processes. In response, GAO interviewed OMB and agency officials and reviewed agency IQA guidelines, related documents, and Web sites."
Date: August 23, 2006
Creator: United States. Government Accountability Office.
Object Type: Report
System: The UNT Digital Library
Accurate labeling of the light-actinide O4,5 ionization edges (open access)

Accurate labeling of the light-actinide O4,5 ionization edges

In this short article the accurate labeling of the O4,5 edges of the light actinides is addressed. The O4 and O5 edges are both contained in what is termed the ''giant resonance'' and the smaller ''pre-peak'' that is observed is a consequence of first-order perturbation by the 5d spin-orbit interaction. Thus, the small prepeak in the actinide 5d {yields} 5f transition should not be labeled the O5 peak, but rather the {Delta}S=1 peak.
Date: August 23, 2006
Creator: Moore, K & der Laan, G v
Object Type: Article
System: The UNT Digital Library
Development of Nanofluidic Cells for Ultrafast X-ray Studies of Water (open access)

Development of Nanofluidic Cells for Ultrafast X-ray Studies of Water

In order to study the molecular structure and dynamics of liquid water with soft x-ray probes, samples with nanoscale dimensions are needed. This paper describes a simple method for preparing nanofluidic water cells. The idea is to confine a thin layer of water between two silicon nitride windows. The windows are 1 mm x 1 mm and 0.5 mm x 0.5 mm in size and have a thickness of 150 nm. The thickness of the water layer was measured experimentally by probing the infrared spectrum of water in the cells with a Fourier Transform InfraRed (FTIR) apparatus and from soft x-ray static measurements at the Advanced Light Source (ALS) at Lawrence Berkeley National Laboratory. Water layers ranging from 10 nm to more than 2 {micro}m were observed. Evidence for changes in the water structure compared to bulk water is observed in the ultrathin cells.
Date: August 23, 2006
Creator: Irizarry, Melvin E. & /Puerto Rico U., Mayaguez /SLAC
Object Type: Article
System: The UNT Digital Library
Remaining Sites Verification Package for the 132-F-1, 141-F Chronic Feeding Sheep Barn, Waste Site Reclassification Form 2006-029 (open access)

Remaining Sites Verification Package for the 132-F-1, 141-F Chronic Feeding Sheep Barn, Waste Site Reclassification Form 2006-029

The 132-F-1 site is the former location of the 141-F Chronic Feeding Sheep Barn that was part of the experimental animal farm at the 100-F Area. It was an L-shaped concrete block building with a concrete floor and concrete animal pens located both inside and outside the building. The 141-F Building was demolished in 1977 following relocation of animal research to the 300 Area. The results of verification sampling demonstrated that residual contaminant concentrations do not preclude any future uses and allow for unrestricted use of shallow zone soils. The results also showed that residual contaminant concentrations are protective of groundwater and the Columbia River.
Date: August 23, 2006
Creator: Dittmer, L. M.
Object Type: Report
System: The UNT Digital Library
Simulations of dynamic crack propagation in brittle materials using nodal cohesive forces and continuum damage mechanics in the distinct element code LDEC (open access)

Simulations of dynamic crack propagation in brittle materials using nodal cohesive forces and continuum damage mechanics in the distinct element code LDEC

Experimental data indicates that the limiting crack speed in brittle materials is less than the Rayleigh wave speed. One reason for this is that dynamic instabilities produce surface roughness and microcracks that branch from the main crack. These processes increase dissipation near the crack tip over a range of crack speeds. When the scale of observation (or mesh resolution) becomes much larger than the typical sizes of these features, effective-medium theories are required to predict the coarse-grained fracture dynamics. Two approaches to modeling these phenomena are described and used in numerical simulations. The first approach is based on cohesive elements that utilize a rate-dependent weakening law for the nodal cohesive forces. The second approach uses a continuum damage model which has a weakening effect that lowers the effective Rayleigh wave speed in the material surrounding the crack tip. Simulations in this paper show that while both models are capable of increasing the energy dissipated during fracture when the mesh size is larger than the process zone size, only the continuum damage model is able to limit the crack speed over a range of applied loads. Numerical simulations of straight-running cracks demonstrate good agreement between the theoretical predictions of the combined …
Date: August 23, 2006
Creator: Block, G I; Rubin, M B; Morris, J P & Berryman, J G
Object Type: Article
System: The UNT Digital Library
Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 27, Ed. 1 Wednesday, August 23, 2006 (open access)

Cherokeean Herald (Rusk, Tex.), Vol. 157, No. 27, Ed. 1 Wednesday, August 23, 2006

Weekly newspaper from Rusk, Texas that includes local, state and national news along with extensive advertising.
Date: August 23, 2006
Creator: Whitehead, Marie
Object Type: Newspaper
System: The Portal to Texas History

[Hand dropping seeds]

Photograph of a man with a tattooed arm dropping small seeds into containers of soil.
Date: August 23, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Planting seeds]

Photograph of a farmer tending trays of growing vegetables.
Date: August 23, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Reaching into container of seeds]

Photograph of a hand reaching into a bowl of small, brown seeds.
Date: August 23, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Newly sprouting micro vegetables]

Newly sprouting micro vegetables in soil. Thanks to a new combined organic and artisan technique with technology, Mexican grower Salvador Huiza waters, sows, and cuts thousands of micro vegetables in a matter of hours in the greenhouse where he works north of Fort Worth, Texas. The harvest of these miniature vegetables, obtained through a procedure where water and earth are used without pesticides, is drawing the attention of restaurants and markets in the area. "The difference is specifically in the flavor; it is much more concentrated than conventional vegetables,” Huiza points out. For a few months he is in charge of the growth of more than 20 varieties of miniature vegetables in the greenhouse Greens Genes.
Date: August 23, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Working with container of micro vegetables]

A man with gloves works with micro vegetables in a container. Thanks to a new combined organic and artisan technique with technology, Mexican grower Salvador Huiza waters, sows, and cuts thousands of micro vegetables in a matter of hours in the greenhouse where he works north of Fort Worth, Texas. The harvest of these miniature vegetables, obtained through a procedure where water and earth are used without pesticides, is drawing the attention of restaurants and markets in the area. "The difference is specifically in the flavor; it is much more concentrated than conventional vegetables,” Huiza points out. For a few months he is in charge of the growth of more than 20 varieties of miniature vegetables in the greenhouse Greens Genes.
Date: August 23, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library

[Close-up of micro vegetables]

Close-up of green, micro vegetables. Thanks to a new combined organic and artisan technique with technology, Mexican grower Salvador Huiza waters, sows, and cuts thousands of micro vegetables in a matter of hours in the greenhouse where he works north of Fort Worth, Texas. The harvest of these miniature vegetables, obtained through a procedure where water and earth are used without pesticides, is drawing the attention of restaurants and markets in the area. "The difference is specifically in the flavor; it is much more concentrated than conventional vegetables,” Huiza points out. For a few months he is in charge of the growth of more than 20 varieties of miniature vegetables in the greenhouse Greens Genes.
Date: August 23, 2006
Creator: Castillo, José L.
Object Type: Photograph
System: The UNT Digital Library
Commission on the Intelligence Capabilities of the United States Regarding Weapons of Mass Destruction: Establishment and Composition (open access)

Commission on the Intelligence Capabilities of the United States Regarding Weapons of Mass Destruction: Establishment and Composition

This report analyzes the establishment and organizational requirements set forth in the presidential mandate, and its relationship to the Federal Advisory Committee Act (FACA).
Date: August 23, 2006
Creator: Smith, Stephanie
Object Type: Report
System: The UNT Digital Library
Greensheet (Houston, Tex.), Vol. 37, No. 341, Ed. 1 Wednesday, August 23, 2006 (open access)

Greensheet (Houston, Tex.), Vol. 37, No. 341, Ed. 1 Wednesday, August 23, 2006

Free weekly newspaper that includes business and classified advertising.
Date: August 23, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Greensheet (Dallas, Tex.), Vol. 30, No. 134, Ed. 1 Wednesday, August 23, 2006 (open access)

The Greensheet (Dallas, Tex.), Vol. 30, No. 134, Ed. 1 Wednesday, August 23, 2006

Free weekly newspaper that includes business and classified advertising.
Date: August 23, 2006
Creator: unknown
Object Type: Newspaper
System: The Portal to Texas History
The Genome of Deep-Sea Vent Chemolithoautotroph Thiomicrospiracrunogena XCL-2 (open access)

The Genome of Deep-Sea Vent Chemolithoautotroph Thiomicrospiracrunogena XCL-2

Presented here is the complete genome sequence ofThiomicrospira crunogena XCL-2, representative of ubiquitouschemolithoautotrophic sulfur-oxidizing bacteria isolated from deep-seahydrothermal vents. This gammaproteobacterium has a single chromosome(2,427,734 bp), and its genome illustrates many of the adaptations thathave enabled it to thrive at vents globally. It has 14 methyl-acceptingchemotaxis protein genes, including four that may assist in positioningit in the redoxcline. A relative abundance of CDSs encoding regulatoryproteins likely control the expression of genes encoding carboxysomes,multiple dissolved inorganic nitrogen and phosphate transporters, as wellas a phosphonate operon, which provide this species with a variety ofoptions for acquiring these substrates from the environment. T. crunogenaXCL-2 is unusual among obligate sulfur oxidizing bacteria in relying onthe Sox system for the oxidation of reduced sulfur compounds. A 38 kbprophage is present, and a high level of prophage induction was observed,which may play a role in keeping competing populations of close relativesin check. The genome has characteristics consistent with an obligatelychemolithoautotrophic lifestyle, including few transporters predicted tohave organic allocrits, and Calvin-Benson-Bassham cycle CDSs scatteredthroughout the genome.
Date: August 23, 2006
Creator: Scott, Kathleen M.; Sievert, Stefan M.; Abril, Fereniki N.; Ball,Lois A.; Barrett, Chantell J.; Blake, Rodrigo A. et al.
Object Type: Article
System: The UNT Digital Library
INVESTIGATION OF MIS ITEM 011589A AND 3013 CONTAINERS HAVING SIMILAR CHARACTERISTICS (open access)

INVESTIGATION OF MIS ITEM 011589A AND 3013 CONTAINERS HAVING SIMILAR CHARACTERISTICS

Recent testing has identified the presence of hydrogen and oxygen in MIS Item 011589A. This isolated observation has effectuated concern regarding the potential for flammable gas mixtures in containers in the storage inventory. This study examines the known physicochemical characteristics of MIS Item 011589A and queries the ISP Database for items that are most similar or potentially similar. Items identified as most similar are believed to have the highest probability of being chemically and structurally identical to MIS Item 011589A. Items identified as potentially like MIS Item 011589A have some attributes in common, have the potential to generate gases, but have a lower probability of having similar gas generating characteristics. MIS Item 011589A is an oxide that was generated prior to 1990 at Rocky Flats in Building 707. It was associated with foundry processing and had an actinide assay of approximately 77%. Prompt gamma analysis of MIS Item 011589A indicated the presence of chloride, fluorine, magnesium, sodium, and aluminum. Queries based on MIS representation classification and process of origin were applied to the ISP Database. Evaluation criteria included binning classification (i.e., innocuous, pressure, or pressure and corrosion), availability of prompt gamma analyses, presence of chlorine and magnesium, percentage of chlorine …
Date: August 23, 2006
Creator: Friday, G
Object Type: Report
System: The UNT Digital Library
Semiconductor quantum dot scintillation under gamma-ray irradiation (open access)

Semiconductor quantum dot scintillation under gamma-ray irradiation

We recently demonstrated the ability of semiconductor quantum dots to convert alpha radiation into visible photons. In this letter, we report on the scintillation of quantum dots under gamma-ray irradiation, and compare the energy resolution of the 59 keV line of Americium 241 obtained with our quantum dot-glass nanocomposite material to that of a standard sodium iodide scintillator. A factor 2 improvement is demonstrated experimentally and interpreted theoretically using a combination of energy-loss and photon transport models. These results demonstrate the potential of quantum dots for room-temperature gamma-ray detection, which has applications in medical imaging, environmental monitoring, as well as security and defense. Present technology in gamma radiation detection suffers from flexibility and scalability issues. For example, bulk Germanium provides fine energy resolution (0.2% energy resolution at 1.33 MeV) but requires operation at liquid nitrogen temperature. On the other hand, Cadmium-Zinc-Telluride is a good room temperature detector ( 1% at 662 keV) but the size of the crystals that can be grown is limited to a few centimeters in each direction. Finally, the most commonly used scintillator, Sodium Iodide (NaI), can be grown as large crystals but suffers from a lack of energy resolution (7% energy resolution at 662 keV). …
Date: August 23, 2006
Creator: Letant, S E & Wang, T
Object Type: Article
System: The UNT Digital Library
Final Report on subcontract B551021: Optimal AMG interpolation and Convergence theory (open access)

Final Report on subcontract B551021: Optimal AMG interpolation and Convergence theory

The goal of this project is to implement and study various techniques for the construction of Algebraic Multigrid Methods (AMG) for the solution of positive definite linear systems arising from the discretizations of elliptic partial differential equations (PDEs). Both theoretical as well as practical implementation of the methods that we have developed are based on compatible relaxation and energy minimization.
Date: August 23, 2006
Creator: Zikatanov, L
Object Type: Report
System: The UNT Digital Library
Laboratory Investigation of Organic Aerosol Formation from Aromatic Hydrocarbons (open access)

Laboratory Investigation of Organic Aerosol Formation from Aromatic Hydrocarbons

Our work for this DOE funded project includes: (1) measurements of the kinetics and mechanism of the gas-phase oxidation reactions of the aromatic hydrocarbons initiated by OH; (2) measurements of aerosol formation from the aromatic hydrocarbons; and (3) theoretical studies to elucidate the OH-toluene reaction mechanism using quantum-chemical and rate theories.
Date: August 23, 2006
Creator: Molina, Luisa T.; Molina, Mario J. & Zhang, Renyi
Object Type: Report
System: The UNT Digital Library
First X-ray Fluorescence MicroCT Results from Micrometeorites at SSRL (open access)

First X-ray Fluorescence MicroCT Results from Micrometeorites at SSRL

X-ray fluorescence microCT (computed tomography) is a novel technique that allows non-destructive determination of the 3D distribution of chemical elements inside a sample. This is especially important in samples for which sectioning is undesirable either due to the risk of contamination or the requirement for further analysis by different characterization techniques. Developments made by third generation synchrotron facilities and laboratory X-ray focusing systems have made these kinds of measurements more attractive by significantly reducing scan times and beam size. First results from the x-ray fluorescence microCT experiments performed at SSRL beamline 6-2 are reported here. Beamline 6-2 is a 54 pole wiggler that uses a two mirror optical system for focusing the x-rays onto a virtual source slit which is then reimaged with a set of KB mirrors to a (2 x 4) {micro}{sup 2} beam spot. An energy dispersive fluorescence detector is located in plane at 90 degrees to the incident beam to reduce the scattering contribution. A PIN diode located behind the sample simultaneously measures the x-ray attenuation in the sample. Several porous micrometeorite samples were measured and the reconstructed element density distribution including self-absorption correction is presented. Ultimately, this system will be used to analyze particles from …
Date: August 23, 2006
Creator: Ignatyev, K.; Huwig, K.; Harvey, R.; Ishii, H.; Bradley, J.; Luening, K. et al.
Object Type: Article
System: The UNT Digital Library
Terascale Optimal PDE Simulations (TOPS) Center (open access)

Terascale Optimal PDE Simulations (TOPS) Center

This report covers the period from Oct. 2002 to Sep. 2004 when Old Dominion University (ODU) was the lead institution for the TOPS ISIC, until in Oct. 2004 Columbia University replaced ODU as the lead institution. The TOPS members from ODU focused on various aspects of the linear and nonlinear solver infrastructure required by the partial differential equations simulation codes, working directly with SciDAC teams from the Fusion Energy Sciences program: the Center for Extended agnetohydrodynamic Modeling (CEMM) at Princeton, and with the Center for Magnetic Reconnection Studies (CMRS) at University of New Hampshire. With CEMM we worked with their MHD simulation code, called M3D, which is semi-implicit, requiring linear solves but no onlinear solves. We contributed several improvements to their current semi-implicit code. Among these was the use of multilevel reconditioning, which provides optimal scaling. This was done through the multigrid preconditioner available in Hypre, another major solver package available in TOPS. We also provided them direct solver functionality for their linear solves since they may be required for more accurate solutions in some regimes. With the CMRS group, we implemented a fully implicit parallel magnetic reconnection simulation code, built on top of PETSc. Our first attempt was a …
Date: August 23, 2006
Creator: Pothen, Alex
Object Type: Report
System: The UNT Digital Library
A Collection of Articles Reprinted from Science & Technology Review on University Relations Program (open access)

A Collection of Articles Reprinted from Science & Technology Review on University Relations Program

This month's issue has the following articles: (1) The Power of Partnership--Livermore researchers forge strategic collaborations with colleagues from other University of California campuses to further science and better protect the nation; (2) Collaborative Research Prepares Our Next-Generation Scientists and Engineers--Commentary by Laura R. Gilliom; (3) Next-Generation Scientists and Engineers Tap Lab's Resources--University of California Ph.D. candidates work with Livermore scientists and engineers to conduct fundamental research as part of their theses; (4) The Best and the Brightest Come to Livermore--The Lawrence Fellowship Program attracts the most sought-after postdoctoral researchers to the Laboratory; and (5) Faculty on Sabbatical Find a Good Home at Livermore--Faculty members from around the world come to the Laboratory as sabbatical scholars.
Date: August 23, 2006
Creator: Radousky, H; Rennie, G & Henke, A
Object Type: Report
System: The UNT Digital Library
Seminole Sentinel (Seminole, Tex.), Vol. 97, No. 91, Ed. 1 Wednesday, August 23, 2006 (open access)

Seminole Sentinel (Seminole, Tex.), Vol. 97, No. 91, Ed. 1 Wednesday, August 23, 2006

Semiweekly newspaper from Seminole, Texas that includes local, state, and national news along with extensive advertising.
Date: August 23, 2006
Creator: Wright, Dustin
Object Type: Newspaper
System: The Portal to Texas History