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70193-Influence of Clastic Dikes on Vertical Migration of Contaminants in the Vadose Zonde at Hanford

Description: The purpose of this study was to examine the hypothesis that clastic dikes could form a preferential flow path through the vadose zone to the water table at the Hanford Site. Clastic dikes are subvertical structures that form within sedimentary sequences after deposition and cut across the original sedimentary layers. They are common throughout the Hanford Site, often occurring in organized polygonal networks. In the initial phase of the project, we analyzed the large-scale geometry of the clastic dikes and developed an algorithm for simulating their spatial distribution. This result will be useful in providing maps of the potential distribution of clastic dikes in areas where they are not exposed at the surface (e.g., where covered by windblown sand or construction of facilities like tank farms at the surface). In addition to the study of the large-scale distribution of the dikes, a major focus of the project was on field, laboratory, and modeling studies of the hydrogeological properties of the clastic dikes and the effect that they have on transport of water through the vadose zone. These studies were performed at two field locations at the Hanford Site. We performed an extensive series of field and laboratory measurements of a large number of samples from the clastic dikes, linked with infrared (IR) and visual imagery of the clastic dikes and surrounding matrix. We developed a series of correlations from the sample data that allowed us to estimate the unsaturated hydraulic conductivity of the dike and matrix at an extremely high resolution (approximately 1 mm). The resulting grids, each of which measured several meters on a side and included nearly four million grid nodes, were used to study the distribution of moisture between the clastic dike and surrounding matrix, as well as the relative velocities that moisture would have through the ...
Date: April 7, 2004
Creator: Murray, Christopher J; Ward, Anderson L. & Wilson, John L.
Partner: UNT Libraries Government Documents Department

Afghanistan: Narcotics and U.S. Policy

Description: This report describes the structure and development of the narcotics trade in Afghanistan and explores its relevance to Afghan, U.S., and international security interests, including the 9/11 Commission’s recommendation that the United States make a long term commitment to the stability and security of Afghanistan. The report provides current statistical information on the opium trade, profiles its various participants, explores alleged narco-terrorist linkages, and reviews the U.S. and international policy response since late 2001. The report also considers current policy debates regarding the role of the U.S. military in future counternarcotics operations in Afghanistan; planned opium poppy eradication; and funding issues for Congress.
Date: December 7, 2004
Creator: Blanchard, Christopher M.
Partner: UNT Libraries Government Documents Department

Age of an Indonesian Fossil Tooth Determined by Electron Paramagnetic Resonance

Description: The first fossil hominid tooth recovered during 1999 excavations from the Cisanca River region in West Java, Indonesia, was associated with a series of bovid teeth from a single individual that was recovered 190 cm beneath the hominid tooth. The age of the fossil bovid teeth was determined using electron paramagnetic resonance (EPR) analysis as part of an effort to bracket the age of the hominid tooth. The EPR-derived age of the bovid teeth is (5.16 {+-} 2.01) x 10{sup 5} years. However, the age estimate reported here is likely an underestimate of the actual age of deposition since evidence of heating was detected in the EPR spectra of the bovid teeth, and the heating may have caused a decrease in the intensity of EPR components on which the age calculation is based.
Date: April 7, 2004
Creator: Bogard, JS
Partner: UNT Libraries Government Documents Department

Alaska Native Allotments: Conflicts with Utility Rights-of-way Have Not Been Resolved through Existing Remedies

Description: A letter report issued by the Government Accountability Office with an abstract that begins "In 1906, the Alaska Native Allotment Act authorized the Secretary of the Interior to allot individual Alaska Natives (Native) a homestead of up to 160 acres. The validity of some of Copper Valley Electric Association's (Copper Valley) rights-of-way within Alaska Native allotments is the subject of ongoing dispute; in some cases the allottees assert that Copper Valley's electric lines trespass on their land. The Department of the Interior's (Interior) Bureau of Land Management (BLM) and Bureau of Indian Affairs (BIA) are responsible for granting rights-of-way and handling disputes between allotees and holders of rights-of-way. GAO determined (1) the number of conflicts between Native allotments and Copper Valley rights-of-way and the factors that contributed to these conflicts, (2) the extent to which existing remedies have been used to resolve these conflicts, and (3) what legislative alternatives, if any, could be considered to resolve these conflicts."
Date: September 7, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

American Community Survey: Key Unresolved Issues

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Congress asked GAO to review operational and programmatic aspects of the Census Bureau's ACS that will affect the reliability of small geographic area data. The ACS will be a mail survey of about 3 million households annually, whose results will be cumulated over 5 years to produce estimates that will replace information previously provided by the Decennial Census long form. In addition, annual data will be published for geographic areas with 65,000+ populations and as 3-year averages for areas with populations of 20,000 to 65,000. Annual data will be published beginning in 2006 with data for 2005. The 5-year averages for 2008-12 will provide data for small geographic areas."
Date: October 7, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Analysis of Long-range Clean Energy Investment Scenarios forEritrea, East Africa

Description: We discuss energy efficiency and renewable energy investments in Eritrea from the strategic long-term economic perspective of meeting Eritrea's sustainable development goals and reducing greenhouse gas emissions. Energy efficiency and renewable energy are potentially important contributors to national productive capital accumulation, enhancement of the environment, expansion of energy services, increases in household standard of living, and improvements in health. In this study we develop a spreadsheet model for calculating some of the national benefits and costs of different levels of investment in energy efficiency and renewable energy. We then present the results of the model in terms of investment demand and investment scenario curves. These curves express the contribution that efficiency and renewable energy projects can make in terms of reduced energy sector operating expenses, and reduced carbon emissions. We provide demand and supply curves that show the rate of return, the cost of carbon emissions reductions vs. supply, and the evolution of the marginal carbon emissions per dollar of GDP for different investment levels and different fuel-type subsectors.
Date: May 7, 2004
Creator: Van Buskirk, Robert D.
Partner: UNT Libraries Government Documents Department

Analysis of Recombination Processes in 0.5 - 0.6eV Epitaxial GaInAsSb Lattice-Matched to GaSb

Description: After a brief introduction and work motivation, static and dynamic methods for minority carrier lifetime measurements will be compared. Data on recombination velocity at heterointerfaces for both p-type and n-type quaternaries will be summarized. Radiative recombination and effect of photon recycling will be considered in detail.
Date: June 7, 2004
Creator: Donetsky, D; Anikeev, S; Ning, G; Belenky, G; Luryi, S; Wang, CA et al.
Partner: UNT Libraries Government Documents Department

Archaeofaunal insights on pinniped-human interactions in the northeastern Pacific

Description: Human exploitation of pinnipeds has considerable antiquity but shows increasing impacts on population numbers in the Holocene. Pinnipeds are a rich source of fat as well as protein. A few well-documented cases of regional extirpation of seals and sea lions by non-industrial peoples exist. The northeastern Pacific region, from southern California to Alaska, has yielded archaeological evidence for distributions and abundances of eared seals that differs markedly from historically documented biogeography. This is especially true of the northern fur seal (Callorhinus ursinus), among the most common pinnipeds in many archaeological sites from the Santa Barbara Channel area through to Kodiak Islands. This chapter reviews contemporary eared seal biogeography, evidence for the earlier timing and extent, of occurrence of northern fur seals along the northeastern Pacific coast, zooarchaeological and isotopic evidence for their foraging and probable maintenance of rookeries in lower latitudes, and for their disappearance from the southernmost part of their ancient distribution well before European contact. It also reviews ongoing debates over the behavioral ecology of ancient fur seals and over humans role in contributing to their disappearance.
Date: February 7, 2004
Creator: Gifford-Gonzales, D; Newsome, S; Koch, P; Guilderson, T; Snodgrass, J & Burton, R
Partner: UNT Libraries Government Documents Department

Assessment of Renal Ischemia By Optical Spectroscopy

Description: Introduction: No reliable method currently exists for quantifying the degree of warm ischemia in kidney grafts prior to transplantation. We describe a method for evaluating pretransplant warm ischemia time using optical spectroscopic methods. Methods: Lewis rat kidney vascular pedicles were clamped unilaterally in vivo for 0, 5, 10, 20, 30, 60, 90 or 120 minutes; 8 animals were studied at each time point. Injured and contra-lateral control kidneys were then flushed with Euro-Collins solution, resected and placed on ice. 335 nm excitation autofluorescence as well as cross polarized light scattering images were taken of each injured and control kidney using filters of various wavelengths. The intensity ratio of the injured to normal kidneys was compared to ischemia time. Results: Autofluorescence intensity ratios through a 450 nm filter and light scattering intensity ratios through an 800 nm filter both decreased significantly with increasing ischemia time (p < 0.0001 for each method, one-way ANOVA). All adjacent and non-adjacent time points between 0 and 90 minutes were distinguishable using one of these two modalities by Fisher's PLSD. Conclusions: Optical spectroscopic methods can accurately quantify warm ischemia time in kidneys that have been subsequently hypothermically preserved. Further studies are needed to correlate results with physiological damage and posttransplant performance.
Date: January 7, 2004
Creator: Fitzgerald, J T; Demos, S; Michalopoulou, A; Pierce, J L & Troppmann, C
Partner: UNT Libraries Government Documents Department

Bills and Resolutions: Examples of How Each Kind Is Used

Description: This report briefly describes the process by which Congress seeks to pass a law. During this process Congress uses a bill or joint resolution, which must be passed by both houses in identical form, that is then presented to the President for his approval or disapproval.
Date: December 7, 2004
Creator: Beth, Richard S.
Partner: UNT Libraries Government Documents Department

Biobased Products: Improved USDA Management Would Help Agencies Comply with Farm Bill Purchasing Requirements

Description: A letter report issued by the General Accounting Office with an abstract that begins "The federal government spends more than $230 billion annually for products and services to conduct its operations. Through its purchasing decisions, it has the opportunity to affirm its policies and goals, including those related to purchases of biobased products, as set out in the 2002 farm bill. A biobased product is a commercial or industrial product, other than food or feed that is composed of, in whole or part, biological products, renewable domestic agricultural materials, or forestry materials. GAO examined (1) actions the U.S. Department of Agriculture (USDA) and other agencies have taken to carry out farm bill requirements for purchasing biobased products, (2) additional actions that may be needed to implement the requirements, and (3) views of stakeholders on the need for and costs of testing biobased products. GAO interviewed officials from USDA, major procuring agencies, testing entities, interested associations, and 15 manufacturers of biobased products."
Date: April 7, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Bioremediation of Petroleum and Radiological Contaminated Soils at the Savannah River Site: Laboratory to Field Scale Applications

Description: In the process of Savannah River Site (SRS) operations limited amounts of waste are generated containing petroleum, and radiological contaminated soils. Currently, this combination of radiological and petroleum contaminated waste does not have an immediate disposal route and is being stored in low activity vaults. SRS developed and implemented a successful plan for clean up of the petroleum portion of the soils in situ using simple, inexpensive, bioreactor technology. Treatment in a bioreactor removes the petroleum contamination from the soil without spreading radiological contamination to the environment. This bioreactor uses the bioventing process and bioaugmentation or the addition of the select hydrocarbon degrading bacteria. Oxygen is usually the initial rate-limiting factor in the biodegradation of petroleum hydrocarbons. Using the bioventing process allowed control of the supply of nutrients and moisture based on petroleum contamination concentrations and soil type. The results of this work have proven to be a safe and cost-effective means of cleaning up low level radiological and petroleum-contaminated soil. Many of the other elements of the bioreactor design were developed or enhanced during the demonstration of a ''biopile'' to treat the soils beneath a Polish oil refinery's waste disposal lagoons. Aerobic microorganisms were isolated from the aged refinery's acidic sludge contaminated with polycyclic aromatic hydrocarbons (PAHs). Twelve hydrocarbon-degrading bacteria were isolated from the sludge. The predominant PAH degraders were tentatively identified as Achromobacter, Pseudomonas Burkholderia, and Sphingomonas spp. Several Ralstonia spp were also isolated that produce biosurfactants. Biosurfactants can enhance bioremediation by increasing the bioavailability of hydrophobic contaminants including hydrocarbons. The results indicated that the diversity of acid-tolerant PAH-degrading microorganisms in acidic oil wastes may be much greater than previously demonstrated and they have numerous applications to environmental restoration. Twelve of the isolates were subsequently added to the bioreactor to enhance bioremediation. In this study we showed that ...
Date: June 7, 2004
Creator: BRIGMON, ROBINL.
Partner: UNT Libraries Government Documents Department

Characterization of liquid phase epitaxial GaAs forblocked-impurity-band far-infrared detectors

Description: GaAs Blocked-Impurity-Band (BIB) photoconductor detectors have the potential to become the most sensitive, low noise detectors in the far-infrared below 45.5 cm{sup -1} (220 {micro}m). We have studied the characteristics of liquid phase epitaxial GaAs films relevant to BIB production, including impurity band formation and the infrared absorption of the active section of the device. Knowledge of the far-infrared absorption spectrum as a function of donor concentration combined with variable temperature Hall effect and resistivity studies leads us to conclude that the optimal concentration for the absorbing layer of a GaAs BIB detector lies between 1 x 10{sup 15} and 6.7 x 10{sup 15} cm{sup -3}. At these concentrations there is significant wavefunction overlap which in turn leads to absorption beyond the 1s ground to 2p bound excited state transition of 35.5 cm{sup -1} (282 {micro}m). There still remains a gap between the upper edge of the donor band and the bottom of the conduction band, a necessity for proper BIB detector operation.
Date: April 7, 2004
Creator: Cardozo, B.L.; Reichertz, L.A.; Beeman, J.W. & Haller, E.E.
Partner: UNT Libraries Government Documents Department

Characterization of the Series 1000 Camera System

Description: The National Ignition Facility requires a compact network addressable scientific grade CCD camera for use in diagnostics ranging from streak cameras to gated x-ray imaging cameras. Due to the limited space inside the diagnostic, an analog and digital input/output option in the camera controller permits control of both the camera and the diagnostic by a single Ethernet link. The system consists of a Spectral Instruments Series 1000 camera, a PC104+ controller, and power supply. The 4k by 4k CCD camera has a dynamic range of 70 dB with less than 14 electron read noise at a 1MHz readout rate. The PC104+ controller includes 16 analog inputs, 4 analog outputs and 16 digital input/output lines for interfacing to diagnostic instrumentation. A description of the system and performance characterization is reported.
Date: April 7, 2004
Creator: Kimbrough, J; Moody, J; Bell, P & Landen, O
Partner: UNT Libraries Government Documents Department

Classification of non-coding RNA using graph representations ofsecondary structure

Description: Some genes produce transcripts that function directly in regulatory, catalytic, or structural roles in the cell. These non-coding RNAs are prevalent in all living organisms, and methods that aid the understanding of their functional roles are essential. RNA secondary structure, the pattern of base-pairing, contains the critical information for determining the three dimensional structure and function of the molecule. In this work we examine whether the basic geometric and topological properties of secondary structure are sufficient to distinguish between RNA families in a learning framework. First, we develop a labeled dual graph representation of RNA secondary structure by adding biologically meaningful labels to the dual graphs proposed by Gan et al [1]. Next, we define a similarity measure directly on the labeled dual graphs using the recently developed marginalized kernels [2]. Using this similarity measure, we were able to train Support Vector Machine classifiers to distinguish RNAs of known families from random RNAs with similar statistics. For 22 of the 25 families tested, the classifier achieved better than 70% accuracy, with much higher accuracy rates for some families. Training a set of classifiers to automatically assign family labels to RNAs using a one vs. all multi-class scheme also yielded encouraging results. From these initial learning experiments, we suggest that the labeled dual graph representation, together with kernel machine methods, has potential for use in automated analysis and classification of uncharacterized RNA molecules or efficient genome-wide screens for RNA molecules from existing families.
Date: June 7, 2004
Creator: Karklin, Yan; Meraz, Richard F. & Holbrook, Stephen R.
Partner: UNT Libraries Government Documents Department

Coast Guard: Key Management and Budget Challenges for Fiscal Year 2005 and Beyond

Description: Testimony issued by the General Accounting Office with an abstract that begins "As the lead federal agency for maritime homeland security within the Department of Homeland Security, the Coast Guard is facing extraordinary, heightened responsibilities to protect America's ports, waterways, and waterside facilities from terrorist attacks. At the same time, the Coast Guard remains responsible for many other programs important to the nation's interests, such as conducting search and rescue and protecting important fishing grounds. Its expanded responsibilities come at a time when budget resources are increasingly constrained, making prioritization among competing agencies and programs an even more critical factor in congressional decision-making. This testimony specifically addresses (1) the most recent trends in both resource usage and performance results for the Coast Guard's homeland security and non-homeland security programs; (2) challenges the agency faces as it proceeds with its Deepwater acquisition program to replace or modernize its key legacy cutters and aircraft; and (3) an overview of the President's fiscal year 2005 budget request for the Coast Guard, focusing on several areas of particular congressional interest."
Date: April 7, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Commemorative Observances: A Chronological List

Description: Historically, national commemorative observances were recommended by Congress through the legislative process. This practice was discontinued by the House of Representatives in January 1995, although the Senate continues to issue sense of the Senate resolutions recommending the establishment of commemoratives. It has now become standard practice for special observances to be designated by a proclamation issued by the President. This report is a chronological list of these proclamations for 1997 and 1998, indicating the proclamation number and its Federal Register citation
Date: September 7, 2004
Creator: Fischer, Hannah
Partner: UNT Libraries Government Documents Department

Compact Probe for Power Detection from the Narrow Side of the Waveguide

Description: Phased array antennas with high directivity have a variety of applications. One of their applications is in RF heating for magnetically confined plasma fusion research. Among these RF heating schemes, waveguide arrays with careful phase control on each waveguide can act as a phased array antenna to deliver megawatts of power for heating fusion plasmas in the lower-hybrid range of frequencies (1 GHz-10 GHz). In order to achieve compactness, it is common to stack reduced height waveguide together to form the waveguide array. As long as the delivered power does not cause arcing in the waveguide, the waveguide height can be quite small. Due to this confined space in a stack of reduced height waveguides, power detection of the incident and reflected wave in the reduced height waveguide is extremely difficult. A new compact probe, which employs current loops, to monitor the incident and reflected wave from the narrow side of the reduced height waveguide has been developed. Its theory and performance will be reported in this paper.
Date: May 7, 2004
Creator: Kung, C.C.; Bernabei, S.; Gumbas, J.; Greenough, N.; Fredd, E.; Wilson, J.R. et al.
Partner: UNT Libraries Government Documents Department