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Comparative genomic analysis reveals a distant liver enhancer upstream of the COUP-TFII gene

Description: COUP-TFII is a central nuclear hormone receptor that tightly regulates the expression of numerous target lipid metabolism genes in vertebrates. However, it remains unclear how COUP-TFII itself is transcriptionally controlled since studies with its promoter and upstream region fail to recapitulate the genes liver expression. In an attempt to identify liver enhancers in the vicinity of COUP-TFII, we employed a comparative genomic approach. Initial comparisons between humans and mice of the 3,470kb gene poor region surrounding COUP-TFII revealed 2,023 conserved non-coding elements. To prioritize a subset of these elements for functional studies, we performed further genomic comparisons with the orthologous pufferfish (Fugu rubripes) locus and uncovered two anciently conserved non-coding sequences (CNS) upstream of COUP-TFII (CNS-62kb and CNS-66kb). Testing these two elements using reporter constructs in liver (HepG2) cells revealed that CNS-66kb, but not CNS-62kb, yielded robust in vitro enhancer activity. In addition, an in vivo reporter assay using naked DNA transfer with CNS-66kb linked to luciferase displayed strong reproducible liver expression in adult mice, further supporting its role as a liver enhancer. Together, these studies further support the utility of comparative genomics to uncover gene regulatory sequences based on evolutionary conservation and provide the substrates to better understand the regulation and expression of COUP-TFII.
Date: August 20, 2004
Creator: Baroukh, Nadine; Ahituv, Nadav; Chang, Jessie; Shoukry, Malak; Afzal, Veena; Rubin, Edward M. et al.
Partner: UNT Libraries Government Documents Department

A survey of state clean energy fund support for biomass

Description: This survey reviews efforts by CESA member clean energy funds to promote the use of biomass as a renewable energy source. For each fund, details are provided regarding biomass eligibility for support, specific programs offering support to biomass projects, and examples of supported biomass projects (if available). For the purposes of this survey, biomass is defined to include bio-product gasification, combustion, co-firing, biofuel production, and the combustion of landfill gas, though not all of the programs reviewed here take so wide a definition. Programs offered by non-CESA member funds fall outside the scope of this survey. To date, three funds--the California Energy Commission, Wisconsin Focus on Energy, and the New York State Energy Research and Development Authority--have offered programs targeted specifically at the use of biomass as a renewable energy source. We begin by reviewing efforts in these three funds, and then proceed to cover programs in other funds that have provided support to biomass projects when the opportunity has arisen, but otherwise do not differentially target biomass relative to other renewable technologies.
Date: August 20, 2004
Creator: Fitzgerald, Garrett; Bolinger, Mark & Wiser, Ryan
Partner: UNT Libraries Government Documents Department

Matter in extremis: Ultrarelativistic nuclear collisions at RHIC

Description: We review the physics of nuclear matter at high energy density and the experimental search for the Quark-Gluon Plasma at the Relativistic Heavy Ion Collider (RHIC). The data obtained in the first three years of the RHIC physics program provide several lines of evidence that a novel state of matter has been created in the most violent, head-on collisions of Au nuclei at {radical}s = 200 GeV. Jet quenching and global measurements show that the initial energy density of the strongly interacting medium generated in the collision is about two orders of magnitude larger than that of cold nuclear matter, well above the critical density for the deconfinement phase transition predicted by lattice QCD. The observed collective flow patterns imply that the system thermalizes early in its evolution, with the dynamics of its expansion consistent with ideal hydrodynamic flow based on a Quark-Gluon Plasma equation of state.
Date: August 20, 2004
Creator: Jacobs, Peter & Wang, Xin-Nian
Partner: UNT Libraries Government Documents Department

Leak Path Factor Evaluation Methodology for Non-Reactor Facilities

Description: The Leak Path Factor (LPF) for a nonreactor nuclear facility is a critical component for the evaluation of the source term used to evaluate the on-site and off-site consequences when an accident produces aerosols containing radioactive powders that propagate through the facility and finally to the outside environment. The Leak Path Factor is defined as the fraction of the airborne radioactive particulate material that is in the respirable size range within the building that escapes via available pathways to the outside environment. This paper presents a methodology to evaluate the LPF for various accident conditions (e.g., seismic event, fire) that could take place in a nonreactor nuclear facility using MELCOR computer code. The methodology presented could enable analysts to efficiently model facilities to assess the magnitude of the LPF by evaluating its various components.
Date: August 20, 2004
Creator: POLIZZI, MARIO
Partner: UNT Libraries Government Documents Department

Job Access and Reverse Commute: Program Status and Potential Effects of Proposed Legislative Changes

Description: Correspondence issued by the Government Accountability Office with an abstract that begins "The Transportation Equity Act for the 21st Century (TEA-21) authorized the Job Access and Reverse Commute (JARC) program to increase the transportation options of low-income workers. The act created JARC, in part because, as the act states, two-thirds of all new jobs were located in the suburbs, while three-fourths of welfare recipients lived in rural areas or central cities, and even in metropolitan areas with excellent public transportation systems, less than half of the jobs were accessible by transit. Under JARC, the Federal Transit Administration (FTA) provides grants to transit agencies, local human service agencies, and others to fill gaps in transportation services for welfare recipients and other low-income individuals. Both houses of Congress have approved separate legislation to reauthorize surface transportation programs including JARC. TEA-21 also required us to provide regular updates on the status of JARC. This letter addresses (1) changes in program funding since fiscal year 1999 and the possible effects of further changes proposed in bills to reauthorize JARC, (2) the possible effects of proposed legislative changes to program coordination requirements, and (3) FTA's 2003 evaluation of the program and plans for future evaluations."
Date: August 20, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Commercial Activities in Schools: Use of Student Data is Limited and Additional Dissemination of Guidance Could Help Districts Develop Policies

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Congress has continuing interest in commercial activities in U.S. public schools. These include product sales, advertising, market research, and the commercial use of personal data about students (such as names, addresses, and telephone numbers) by schools. To update information about commercial activities in schools, Congress asked us to answer the following questions: (1) Since 2000, what statutes and regulations have states enacted and proposed to govern commercial activities in schools? (2) To what extent have districts developed policies implementing amended provisions of the Protection of Pupil Rights Amendment (PPRA) in the No Child Left Behind Act on the use of student data for commercial purposes? (3) What guidance has the Department of Education (Education) disseminated? To answer these questions, we researched state laws, surveyed a national sample of school districts, analyzed policies provided by districts, interviewed officials at Education, and examined its guidance. In addition, we updated findings from the districts we visited in 2000."
Date: August 20, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Medicare Secondary Payer: Improvements Needed to Enhance Debt Recovery Process

Description: A letter report issued by the Government Accountability Office with an abstract that begins "Last year, employer-sponsored group health plans (EGHP) were responsible for most of the nearly $183 million in outstanding Medicare secondary payer (MSP) debt. MSP debts arise when Medicare inadvertently pays for services that are subsequently determined to be the financial responsibility of another. The Centers for Medicare & Medicaid Services (CMS) administers Medicare with the assistance of about 50 contractors that, as part of their duties, are required to recover MSP debt. GAO was asked to determine whether Medicare contractors are appropriately recovering MSP debt. GAO (1) assessed the cost-effectiveness of the current debt recovery system and (2) identified CMS's plans to enhance the recovery process. GAO analyzed workload and budget information and assessed plans to develop a new debt recovery system--the Recovery Management and Accounting System (ReMAS)."
Date: August 20, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Information Technology: FAA Has Many Investment Management Capabilities in Place, but More Oversight of Operational Systems Is Needed

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The Federal Aviation Administration's (FAA) mission is to promote the safe, orderly, and expeditious flow of air traffic in the United States airspace system, commonly referred to as the National Airspace System (NAS). To maintain its ability to effectively carry out this mission FAA embarked, in 1981,on a multi-billion dollar effort to modernize its aging air traffic control (ATC) system, the principle technology component of the NAS. Yet the NAS modernization has continued to be plagued by cost increases, schedule delays, and performance shortfalls. To gain insight into how FAA is meeting its management challenges, congressional requesters asked GAO to evaluate FAA's processes for making IT investment management decisions. The objectives of this review included (1) evaluating FAA's capabilities for managing its IT investments and (2) determining what plans, if any, the agency might have for improving these capabilities."
Date: August 20, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Military Pay: Army Reserve Soldiers Mobilized to Active Duty Experienced Significant Pay Problems

Description: A letter report issued by the Government Accountability Office with an abstract that begins "In light of GAO's November 2003 report highlighting significant pay problems experienced by Army National Guard soldiers mobilized to active duty in support of the global war on terrorism and homeland security, GAO was asked to determine if controls used to pay mobilized Army Reserve soldiers provided assurance that such payments are accurate and timely. GAO's audit used a case study approach to focus on controls over three key areas: processes, people (human capital), and automated systems."
Date: August 20, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Student Consolidation Loans: Further Analysis Could Lead to Enhanced Default Assumptions for Budgetary Cost Estimates

Description: A letter report issued by the Government Accountability Office with an abstract that begins "The number of borrowers consolidating their federal student loans has increased substantially in recent years, with the total amount of loans being consolidated rising from $13 billion in fiscal year 1999 to over $41 billion in fiscal year 2003. This increase in consolidation loan volume and recent interest rate trends have increased the overall estimated long-term cost to the federal government of providing consolidation loans under the Department of Education's (Education) two major student loan programs--the Federal Family Education Loan Program (FFELP) and the William D. Ford Federal Direct Loan Program (FDLP). GAO is providing information on (1) the differences that exist between FFELP and FDLP consolidation loans and borrowers, (2) the extent to which borrowers with student loans under one program obtain consolidation loans under the other, and (3) how FFELP and FDLP borrower and loan characteristics and the movement of loans between the two programs are incorporated into Education's budgetary cost estimates for consolidation loans."
Date: August 20, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

Air Traffic Control: System Management Capabilities Improved, but More Can Be Done to Institutionalize Improvements

Description: A chapter report issued by the Government Accountability Office with an abstract that begins "Since 1981, the Federal Aviation Administration (FAA) has been working to modernize its aging air traffic control (ATC) system. Individual projects have suffered cost increases, schedule delays, and performance shortfalls of large proportions, leading GAO to designate the program a high-risk information technology initiative in 1995. Because the program remains a high risk initiative, GAO was requested to assess FAA's progress in several information technology management areas. This report, one in a series responding to that request, has two objectives: (1) to evaluate FAA's capabilities for developing and acquiring software and systems on its ATC modernization program and (2) to assess the actions FAA has under way to improve these capabilities."
Date: August 20, 2004
Creator: United States. Government Accountability Office.
Partner: UNT Libraries Government Documents Department

9/11 Commission Recommendations: Joint Committee on Atomic Energy - A Model for Congressional Oversight?

Description: This report focuses on that portion of the 9/11 Commission recommendation that urges Congress to consider the model of the Joint Committee on Atomic Energy (JCAE). It provides an outline of the history, structure, and powers of the JCAE and analyzes a number of issues that might be considered by policymakers as they weigh the suitability of the JCAE as a possible model when crafting congressional oversight mechanisms for intelligence.
Date: August 20, 2004
Creator: Davis, Christopher M.
Partner: UNT Libraries Government Documents Department

NUCLEAR-OPTICAL CONVERTERS FOR NEUTRON DETECTION

Description: Nuclear-optical converters (NOC) are fission chambers based upon fission fragment energy conversion to optical radiation in gas luminescent media. The All-Russia Scientific Research Institute of Experimental Physics (VNIIEF) has demonstrated that it is possible to construct nuclear-optical converters with characteristics appropriate for a wide-range of measuring applications including neutron detection in nuclear power plants. These detectors may be used a number of different modes: pulse count, luminescent (equivalent to current mode in ionization detectors), and lasing (essentially a neutron switch). NOCs offer a number of potential advantages over ionization detectors. The detectors require no power supply. Signals are transmitted via light-pipe or fiber optics rather than insulated electrical cable. The detectors are less sensitive to gamma radiation. NOC can produce large signals, obviating the need for pre-amplifiers near the detector. It is possible to construct a single detector which measures flux at many discrete points and at the same time provides total flux along a line containing these discrete points. This paper describes the construction and testing of NOC at VNIIEF; the range of characteristics thought to be reasonably attainable with nuclear-optical converters, and possible applications to nuclear power plant instrumentation.
Date: August 20, 2004
Creator: Sinyanskii, A A; Melnikov, S P; Dovbysh, L E & Johnson, G L
Partner: UNT Libraries Government Documents Department

Simulations of Underground Structures Subjected to Dynamic Loading Using the Distinct Element Method

Description: We present results from an investigation into the stability of underground structures in response to explosive loading. Field tests indicate that structural response can be dominated by the effect of preexisting fractures and faults in the rock mass. Consequently, accurate models of underground structures must take into account plastic deformations across fractures and not simply within the intact portions of the rock mass. The distinct element method (DEM) is naturally suited to simulating such systems because it can explicitly accommodate the blocky nature of natural rock masses. We will discuss details specific to our implementation of the DEM and summarize recent results.
Date: August 20, 2004
Creator: Morris, J P; Bonner, M P & Heuze, F E
Partner: UNT Libraries Government Documents Department

A fourth order accurate adaptive mesh refinement method forpoisson's equation

Description: We present a block-structured adaptive mesh refinement (AMR) method for computing solutions to Poisson's equation in two and three dimensions. It is based on a conservative, finite-volume formulation of the classical Mehrstellen methods. This is combined with finite volume AMR discretizations to obtain a method that is fourth-order accurate in solution error, and with easily verifiable solvability conditions for Neumann and periodic boundary conditions.
Date: August 20, 2004
Creator: Barad, Michael & Colella, Phillip
Partner: UNT Libraries Government Documents Department