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Accounting for Global Climate Model Projection Uncertainty in Modern Statistical Downscaling (open access)

Accounting for Global Climate Model Projection Uncertainty in Modern Statistical Downscaling

Future climate change has emerged as a national and a global security threat. To carry out the needed adaptation and mitigation steps, a quantification of the expected level of climate change is needed, both at the global and the regional scale; in the end, the impact of climate change is felt at the local/regional level. An important part of such climate change assessment is uncertainty quantification. Decision and policy makers are not only interested in 'best guesses' of expected climate change, but rather probabilistic quantification (e.g., Rougier, 2007). For example, consider the following question: What is the probability that the average summer temperature will increase by at least 4 C in region R if global CO{sub 2} emission increases by P% from current levels by time T? It is a simple question, but one that remains very difficult to answer. It is answering these kind of questions that is the focus of this effort. The uncertainty associated with future climate change can be attributed to three major factors: (1) Uncertainty about future emission of green house gasses (GHG). (2) Given a future GHG emission scenario, what is its impact on the global climate? (3) Given a particular evolution of the …
Date: March 17, 2010
Creator: Johannesson, G
System: The UNT Digital Library
Adaptation of the Biolog Phenotype MicroArrayTM Technology to Profile the Obligate Anaerobe Geobacter metallireducens (open access)

Adaptation of the Biolog Phenotype MicroArrayTM Technology to Profile the Obligate Anaerobe Geobacter metallireducens

The Biolog OmniLog? Phenotype MicroArray (PM) plate technology was successfully adapted to generate a select phenotypic profile of the strict anaerobe Geobacter metallireducens (G.m.). The profile generated for G.m. provides insight into the chemical sensitivity of the organism as well as some of its metabolic capabilities when grown with a basal medium containing acetate and Fe(III). The PM technology was developed for aerobic organisms. The reduction of a tetrazolium dye by the test organism represents metabolic activity on the array which is detected and measured by the OmniLog(R) system. We have previously adapted the technology for the anaerobic sulfate reducing bacterium Desulfovibrio vulgaris. In this work, we have taken the technology a step further by adapting it for the iron reducing obligate anaerobe Geobacter metallireducens. In an osmotic stress microarray it was determined that the organism has higher sensitivity to impermeable solutes 3-6percent KCl and 2-5percent NaNO3 that result in osmotic stress by osmosis to the cell than to permeable non-ionic solutes represented by 5-20percent ethylene glycol and 2-3percent urea. The osmotic stress microarray also includes an array of osmoprotectants and precursor molecules that were screened to identify substrates that would provide osmotic protection to NaCl stress. None of the …
Date: May 17, 2010
Creator: Joyner, Dominique; Fortney, Julian; Chakraborty, Romy & Hazen, Terry
System: The UNT Digital Library
Afghanistan: Post-Taliban Governance, Security, and U.S. Policy (open access)

Afghanistan: Post-Taliban Governance, Security, and U.S. Policy

This report discusses the current political state of Iran, focusing particularly on the influence of the Taliban and other militant groups and on the leadership of Afghan President Hamid Karzai. This report also discusses the U.S.-Iran relationship and U.S. efforts under the Obama Administration to provide military, reconstructive, and stabilization aid.
Date: September 17, 2010
Creator: Katzman, Kenneth
System: The UNT Digital Library
Afghanistan: Post-Taliban Governance, Security, and U.S. Policy (open access)

Afghanistan: Post-Taliban Governance, Security, and U.S. Policy

This report discusses the current political state of Iran, focusing particularly on the influence of the Taliban and other militant groups and on the leadership of Afghan President Hamid Karzai. This report also discusses the U.S.-Iran relationship and U.S. efforts under the Obama Administration to provide military, reconstructive, and stabilization aid.
Date: August 17, 2010
Creator: Katzman, Kenneth
System: The UNT Digital Library
Argentina's Defaulted Sovereign Debt: Dealing with the "Holdouts" (open access)

Argentina's Defaulted Sovereign Debt: Dealing with the "Holdouts"

This report reviews Argentina's financial crisis, the bond exchanges of 2005 and 2010, ongoing litigation, prospects for a final solution, related U.S. legislation, and broader policy issues. These include lessons on the effectiveness and cost of Argentina's default strategy, the ability to force sovereigns to meet their debt obligations, and ways to avoid future defaults like Argentina's.
Date: June 17, 2010
Creator: Hornbeck, J. F.
System: The UNT Digital Library
Argentina's Defaulted Sovereign Debt: Dealing with the "Holdouts" (open access)

Argentina's Defaulted Sovereign Debt: Dealing with the "Holdouts"

This report reviews Argentina's financial crisis, the bond exchanges of 2005 and 2010, ongoing litigation, prospects for a final solution, related U.S. legislation, and broader policy issues. These include lessons on the effectiveness and cost of Argentina's default strategy, the ability to force sovereigns to meet their debt obligations, and ways to avoid future defaults like Argentina's.
Date: February 17, 2010
Creator: Hornbeck, J. F.
System: The UNT Digital Library
Authority of State and Local Police to Enforce Federal Immigration Law (open access)

Authority of State and Local Police to Enforce Federal Immigration Law

This report discusses the authority of state and local law enforcement to assist in the enforcement of federal immigration law through the investigation and arrest of persons believed to have violated such laws. It describes current provisions in federal law that permit state and local police to enforce immigration law directly, analyzes major cases concerning the ability of states and localities to assist in immigration enforcement, and briefly examines opinions on the issue by the Office of Legal Counsel (OLC) within the Department of Justice.
Date: September 17, 2010
Creator: Garcia, Michael John & Manuel, Kate M.
System: The UNT Digital Library
Authority of State and Local Police to Enforce Federal Immigration Law (open access)

Authority of State and Local Police to Enforce Federal Immigration Law

This report discusses the authority of state and local law enforcement to assist in the enforcement of federal immigration law through the investigation and arrest of persons believed to have violated such laws. It describes current provisions in federal law that permit state and local police to enforce immigration law directly, analyzes major cases concerning the ability of states and localities to assist in immigration enforcement, and briefly examines opinions on the issue by the Office of Legal Counsel (OLC) within the Department of Justice.
Date: September 17, 2010
Creator: Garcia, Michael John & Manuel, Kate M.
System: The UNT Digital Library
Border Security: Enhanced DHS Oversight and Assessment of Interagency Coordination Is Needed for the Northern Border (open access)

Border Security: Enhanced DHS Oversight and Assessment of Interagency Coordination Is Needed for the Northern Border

A letter report issued by the Government Accountability Office with an abstract that begins "The challenges of securing the U.S.-Canadian border involve the coordination of multiple partners. The results of the Department of Homeland Security's (DHS) efforts to integrate border security among its components and across federal, state, local, tribal, and Canadian partners are unclear. GAO was asked to address the extent to which DHS has (1) improved coordination with state, local, tribal, and Canadian partners; (2) progressed in addressing past federal coordination challenges; and (3) progressed in securing the northern border and used coordination efforts to address existing vulnerabilities. GAO reviewed interagency agreements, strategies, and operational documents that address DHS's reported northern border vulnerabilities such as terrorism. GAO visited four Border Patrol sectors, selected based on threat, and interviewed officials from federal, state, local, tribal, and Canadian agencies operating within these sectors. While these results cannot be generalized, they provided insights on border security coordination."
Date: December 17, 2010
Creator: United States. Government Accountability Office.
System: The UNT Digital Library
CO2 MONITORING FOR DEMAND CONTROLLED VENTILATION IN COMMERCIAL BUILDINGS (open access)

CO2 MONITORING FOR DEMAND CONTROLLED VENTILATION IN COMMERCIAL BUILDINGS

Carbon dioxide (CO{sub 2}) sensors are often deployed in commercial buildings to obtain CO{sub 2} data that are used, in a process called demand-controlled ventilation, to automatically modulate rates of outdoor air ventilation. The objective is to keep ventilation rates at or above design specifications and code requirements and also to save energy by avoiding excessive ventilation rates. Demand controlled ventilation is most often used in spaces with highly variable and sometime dense occupancy. Reasonably accurate CO{sub 2} measurements are needed for successful demand controlled ventilation; however, prior research has suggested substantial measurement errors. Accordingly, this study evaluated: (a) the accuracy of 208 CO{sub 2} single-location sensors located in 34 commercial buildings, (b) the accuracy of four multi-location CO{sub 2} measurement systems that utilize tubing, valves, and pumps to measure at multiple locations with single CO{sub 2} sensors, and (c) the spatial variability of CO{sub 2} concentrations within meeting rooms. The field studies of the accuracy of single-location CO{sub 2} sensors included multi-concentration calibration checks of 90 sensors in which sensor accuracy was checked at multiple CO{sub 2} concentrations using primary standard calibration gases. From these evaluations, average errors were small, -26 ppm and -9 ppm at 760 and 1010 …
Date: March 17, 2010
Creator: Fisk, William J.; Sullivan, Douglas P.; Faulkner, David & Eliseeva, Ekaterina
System: The UNT Digital Library
Comparative Genomics Analysis and Phenotypic Characterization of Shewanella putrefaciens W3-18-1: Anaerobic Respiration, Bacterial Microcompartments, and Lateral Flagella (open access)

Comparative Genomics Analysis and Phenotypic Characterization of Shewanella putrefaciens W3-18-1: Anaerobic Respiration, Bacterial Microcompartments, and Lateral Flagella

Respiratory versatility and psychrophily are the hallmarks of Shewanella. The ability to utilize a wide range of electron acceptors for respiration is due to the large number of c-type cytochrome genes present in the genome of Shewanella strains. More recently the dissimilatory metal reduction of Shewanella species has been extensively and intensively studied for potential applications in the bioremediation of radioactive wastes of groundwater and subsurface environments. Multiple Shewanella genome sequences are now available in the public databases (Fredrickson et al., 2008). Most of the sequenced Shewanella strains were isolated from marine environments and this genus was believed to be of marine origin (Hau and Gralnick, 2007). However, the well-characterized model strain, S. oneidensis MR-1, was isolated from the freshwater lake sediment of Lake Oneida, New York (Myers and Nealson, 1988) and similar bacteria have also been isolated from other freshwater environments (Venkateswaran et al., 1999). Here we comparatively analyzed the genome sequence and physiological characteristics of S. putrefaciens W3-18-1 and S. oneidensis MR-1, isolated from the marine and freshwater lake sediments, respectively. The anaerobic respirations, carbon source utilization, and cell motility have been experimentally investigated. Large scale horizontal gene transfers have been revealed and the genetic divergence between these …
Date: May 17, 2010
Creator: Qiu, D.; Tu, Q.; He, Zhili & Zhou, Jizhong
System: The UNT Digital Library
Comparative Metagenomics of Freshwater Microbial Communities (open access)

Comparative Metagenomics of Freshwater Microbial Communities

Previous analyses of a microbial metagenome from uranium and nitric-acid contaminated groundwater (FW106) showed significant environmental effects resulting from the rapid introduction of multiple contaminants. Effects include a massive loss of species and strain biodiversity, accumulation of toxin resistant genes in the metagenome and lateral transfer of toxin resistance genes between community members. To better understand these results in an ecological context, a second metagenome from a pristine groundwater system located along the same geological strike was sequenced and analyzed (FW301). It is hypothesized that FW301 approximates the ancestral FW106 community based on phylogenetic profiles and common geological parameters; however, even if is not the case, the datasets still permit comparisons between healthy and stressed groundwater ecosystems. Complex carbohydrate metabolism has been almost entirely lost in the stressed ecosystem. In contrast, the pristine system encodes a wide diversity of complex carbohydrate metabolism systems, suggesting that carbon turnover is very rapid and less leaky in the healthy groundwater system. FW301 encodes many (~;;160+) carbon monoxide dehydrogenase genes while FW106 encodes none. This result suggests that the community is frequently exposed to oxygen from aerated rainwater percolating into the subsurface, with a resulting high rate of carbon metabolism and CO production. When …
Date: May 17, 2010
Creator: Hemme, Chris; Deng, Ye; Tu, Qichao; Fields, Matthew; Gentry, Terry; Wu, Liyou et al.
System: The UNT Digital Library
Concerns in Marine Renewable Energy Projects (open access)

Concerns in Marine Renewable Energy Projects

To accelerate the adoption of these emerging marine hydrokinetic technologies, navigational and environmental issues and concerns must be identified and addressed. As hydrokinetic projects move forward, various stakeholders will need to be engaged; one of the key issues that project proponents face as they engage stakeholders is that many conflicting uses and environmental issues are not well-understood. Much of this lack of understanding comes from a limited understanding of the technologies themselves. To address this issue, in September 2008, RE Vision consulting, LLC, was selected by the Department of Energy, under their market acceleration program, to apply a scenario-based assessment approach to the emerging hydrokinetic technology sector. The goal was to improve understanding of potential environmental and navigation impacts of these technologies and focus stakeholders on the critical issues. To meet this goal, the study established baseline scenarios for wave and tidal power conversion at potential future deployment sites. The scenarios captured variations in technical approaches and deployment scales and thus grounded the analysis in realistic constraints. The work conducted under this award provides an important foundation to other market acceleration activities carried out by the DoE and other stakeholders in this sector. The scenarios were then evaluated using a …
Date: June 17, 2010
Creator: Sharon Kramer, Mirko Previsic, Peter Nelson, Sheri Woo
System: The UNT Digital Library
Conservation of Modules but not Phenotype in Bacterial Response to Environmental Stress (open access)

Conservation of Modules but not Phenotype in Bacterial Response to Environmental Stress

Microbes live in changing environments and change their phenotype via gene regulation in response. Although this transcriptional response is important for fitness, very little is known about how it evolves in microbes. We started by asking a number of high-level questions about the evolution of transcriptional phenotype: (1) To what extent is transcriptional response conserved, i.e. do conserved genes respond similarly to the same condition; (2) To what extent are transcriptional modules conserved; and (3) Does there exist a general stress response to a variety of stressors? To illuminate these questions, we analyzed more than 500 microarray experiments across the bacterial domain. We looked for conservation of transcriptional regulation both in close sister species and vastly divergent clades. In addition, we produced and analyzed an extensive in-house compendium of environmental stress data in three metal-reducing bacteria.
Date: May 17, 2010
Creator: Timberlake, Sonia; Joachimiak, Marcin; Joyner, Dominique; Chakraborty, Romy; Baumohl, Jason; Dehal, Paramvir et al.
System: The UNT Digital Library
Continuing Resolutions: Latest Action and Brief Overview of Recent Practices (open access)

Continuing Resolutions: Latest Action and Brief Overview of Recent Practices

This report is divided into two segments. The first section provides the most recent information on the FY2011 continuing resolution. The second segment focuses on the (1) history and recent trends, including the nature, scope, and duration of CRs during the past 35 years; (2) CR types by duration; (3) major substantive legislative provisions included in some CRs; and (4) funding gaps.
Date: December 17, 2010
Creator: Streeter, Sandy
System: The UNT Digital Library
Credit Union Member Business Loans (open access)

Credit Union Member Business Loans

This report discusses about the current legislation, the Promoting Lending to America's Small Business Act of 2009 and the small Business Lending Enhancement Act of 2009 that would provide credit union with expanded business loan authority.
Date: February 17, 2010
Creator: Smale, Pauline
System: The UNT Digital Library
The "Deeming Resolution": A Budget Enforcement Tool (open access)

The "Deeming Resolution": A Budget Enforcement Tool

Deeming resolution" is a term that refers to legislation which is deemed to serve as an annual budget resolution for purposes of establishing enforceable budget levels for a budget cycle. A deeming resolution is used when the House and Senate are late in reaching final agreement on a budget resolution or fail to reach agreement altogether. Either chamber may initiate its own budget enforcement procedures by adopting a "deeming resolution" in the form of a simple resolution. This report describes substantive enforcement procedures associated with the budget resolution, explains the concept of a "deeming resolution," discusses House and Senate action on deeming resolutions, and provides information on a related topic, waiving a bar against the consideration of budgetary legislation for a fiscal year before a budget resolution for that fiscal year has been adopted.
Date: May 17, 2010
Creator: Keith, Robert
System: The UNT Digital Library
Defense Authorization and Appropriations Bills: FY1970-FY2010 (open access)

Defense Authorization and Appropriations Bills: FY1970-FY2010

The passage of the Department of Defense (DOD) authorization and appropriations bills through Congress often does not follow the course laid out in textbooks on legislative procedure. Tracking DOD authorization or appropriations bills can often be confusing and time-consuming. This report is a research aid, which lists the DOD authorization bills (Table 1) and appropriations bills (Table 2) for FY1970-FY2010. This report includes all the pertinent information on the passage of these bills through the legislative process: bill numbers, report numbers, dates reported and passed, recorded vote numbers and vote tallies, dates of passage of the conference reports with their numbers and votes, vetoes, substitutions, dates of final passage, and public law numbers. Key definitions are also included.
Date: February 17, 2010
Creator: Oboroceanu, Mari-Jana
System: The UNT Digital Library
Defense: FY2011 Authorization and Appropriations (open access)

Defense: FY2011 Authorization and Appropriations

The President's FY2011 budget request, released February 1, 2010, included $733.3 billion in new budget authority for national defense. This report discusses and break downs these defense appropriations.
Date: September 17, 2010
Creator: Towell, Pat
System: The UNT Digital Library
A Degaussing Procedure for the QG01 Quadrupole Magnet (open access)

A Degaussing Procedure for the QG01 Quadrupole Magnet

This note describes a degaussing procedure for the QG01 Quadrupole Magnet of the LCLS Injector Beamline and some relevant observations made during the development and testing of this procedure. An important observation is that care must be taken not to cause a current spike when the power supply to the magnet is switched off.
Date: December 17, 2010
Creator: Weidemann, Achim W.
System: The UNT Digital Library
Deployment Effects of Marin Renewable Energy Technologies (open access)

Deployment Effects of Marin Renewable Energy Technologies

Given proper care in siting, design, deployment, operation and maintenance, marine and hydrokinetic technologies could become one of the more environmentally benign sources of electricity generation. In order to accelerate the adoption of these emerging hydrokinetic and marine energy technologies, navigational and environmental concerns must be identified and addressed. All developing hydrokinetic projects involve a wide variety of stakeholders. One of the key issues that site developers face as they engage with this range of stakeholders is that many of the possible conflicts (e.g., shipping and fishing) and environmental issues are not well-understood, due to a lack of technical certainty. In September 2008, re vision consulting, LLC was selected by the Department of Energy (DoE) to apply a scenario-based approach to the emerging wave and tidal technology sectors in order to evaluate the impact of these technologies on the marine environment and potentially conflicting uses. The project’s scope of work includes the establishment of baseline scenarios for wave and tidal power conversion at potential future deployment sites. The scenarios will capture variations in technical approaches and deployment scales to properly identify and characterize environmental impacts and navigational effects. The goal of the project is to provide all stakeholders with an …
Date: June 17, 2010
Creator: Polagye, Brian & Previsic, Mirko
System: The UNT Digital Library
Deployment Effects of Marine Renewable Energy Technologies: Wave Energy Scenarios (open access)

Deployment Effects of Marine Renewable Energy Technologies: Wave Energy Scenarios

Given proper care in siting, design, deployment, operation and maintenance, wave energy conversion could become one of the more environmentally benign sources of electricity generation. In order to accelerate the adoption of these emerging hydrokinetic and marine energy technologies, navigational and environmental concerns must be identified and addressed. All developing hydrokinetic projects involve a wide variety of stakeholders. One of the key issues that site developers face as they engage with this range of stakeholders is that, due to a lack of technical certainty, many of the possible conflicts (e.g., shipping and fishing) and environmental issues are not well-understood,. In September 2008, re vision consulting, LLC was selected by the Department of Energy (DoE) to apply a scenario-based assessment to the emerging hydrokinetic technology sector in order to evaluate the potential impact of these technologies on the marine environment and navigation constraints. The project’s scope of work includes the establishment of baseline scenarios for wave and tidal power conversion at potential future deployment sites. The scenarios capture variations in technical approaches and deployment scales to properly identify and characterize environmental effects and navigational effects. The goal of the project is to provide all stakeholders with an improved understanding of the …
Date: June 17, 2010
Creator: Previsic, Mirko
System: The UNT Digital Library
Development of a Model, Metal-reducing Microbial Community for a System Biology Level Assessment of Desulfovibrio vulgaris as part of a Community (open access)

Development of a Model, Metal-reducing Microbial Community for a System Biology Level Assessment of Desulfovibrio vulgaris as part of a Community

One of the largest experimental gaps is between the simplicity of pure cultures and the complexity of open environmental systems, particularly in metal-contaminated areas. These microbial communities form ecosystem foundations, drive biogeochemical processes, and are relevant for biotechnology and bioremediation. A model, metal-reducing microbial community was constructed as either syntrophic or competitive to study microbial cell to cell interactions, cell signaling and competition for resources. The microbial community was comprised of the metal-reducing Desulfovibrio vulgaris Hildenborough and Geobacter sulfurreducens PCA. Additionally, Methanococcus maripaludis S2 was added to study complete carbon reduction and maintain a low hydrogen partial pressure for syntrophism to occur. Further, considerable work has been published on D. vulgaris and the D. vulgaris/ Mc. maripaludis co-culture both with and without stress. We are extending this work by conducting the same stress conditions on the model community. Additionally, this comprehensive investigation includes physiological and metabolic analyses as well as specially designed mRNA microarrays with the genes for all three organisms on one slide so as to follow gene expression changes in the various cultivation conditions as well as being comparable to the co- and individual cultures. Further, state-of -the-art comprehensive AMT tag proteomics allows for these comparisons at the …
Date: May 17, 2010
Creator: Elias, Dwayne; Schadt, Christopher; Miller, Lance; Phelps, Tommy; Brown, S. D.; Arkin, Adam et al.
System: The UNT Digital Library
Development of Crystal-Tolerant High-Level Waste Glasses (open access)

Development of Crystal-Tolerant High-Level Waste Glasses

Twenty five glasses were formulated. They were batched from HLW AZ-101 simulant or raw chemicals and melted and tested with a series of tests to elucidate the effect of spinel-forming components (Ni, Fe, Cr, Mn, and Zn), Al, and noble metals (Rh2O3 and RuO2) on the accumulation rate of spinel crystals in the glass discharge riser of the high-level waste (HLW) melter. In addition, the processing properties of glasses, such as the viscosity and TL, were measured as a function of temperature and composition. Furthermore, the settling of spinel crystals in transparent low-viscosity fluids was studied at room temperature to access the shape factor and hindered settling coefficient of spinel crystals in the Stokes equation. The experimental results suggest that Ni is the most troublesome component of all the studied spinel-forming components producing settling layers of up to 10.5 mm in just 20 days in Ni-rich glasses if noble metals or a higher concentration of Fe was not introduced in the glass. The layer of this thickness can potentially plug the bottom of the riser, preventing glass from being discharged from the melter. The noble metals, Fe, and Al were the components that significantly slowed down or stopped the accumulation …
Date: December 17, 2010
Creator: Matyas, Josef; Vienna, John D.; Schaible, Micah J.; Rodriguez, Carmen P.; Crum, Jarrod V.; Arrigoni, Alyssa L. et al.
System: The UNT Digital Library