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Putting downward pressure on natural gas prices: The impact of renewable energy and energy efficiency

Description: Increased deployment of renewable energy (RE) and energy efficiency (EE) is expected to reduce natural gas demand and in turn place downward pressure on gas prices. A number of recent modeling studies include an evaluation of this effect. Based on data compiled from those studies summarized in this paper, each 1% reduction in national natural gas demand appears likely to lead to a long-term average wellhead gas price reduction of 0.75% to 2.5%, with some studies predicting even more sizable reductions. Reductions in wellhead prices will reduce wholesale and retail electricity rates, and will also reduce residential, commercial, and industrial gas bills. We further find that many of these studies appear to represent the potential impact of RE and EE on natural gas prices within the bounds of current knowledge, but that current knowledge of how to estimate this effect is extremely limited. While more research is therefore needed, existing studies suggest that it is not unreasonable to expect that any increase in consumer electricity costs attributable to RE and/or EE deployment may be substantially offset by the corresponding reduction in delivered natural gas prices. This effect represents a wealth transfer (from natural gas producers to consumers) rather than a net gain in social welfare, and is therefore not a standard motivation for policy intervention on economic grounds. Reducing gas prices and thereby redistributing wealth may still be of importance in policy circles, however, and may be viewed in those circles as a positive ancillary effect of RE and EE deployment.
Date: May 20, 2004
Creator: Wiser, Ryan; Bolinger, Mark & St. Clair, Matthew
Partner: UNT Libraries Government Documents Department

A possible connection between thermal comfort and health

Description: It is a well-established fact that cardiovascular health requires periodic exercise during which the human body often experiences significant physical discomfort. It is not obvious to the exerciser that the short-term pain and discomfort has a long-term positive health impact. Many cultures have well-established practices that involve exposing the body to periodic thermal discomfort. Scandinavian saunas and American Indian sweat lodges are two examples. Both are believed to promote health and well-being. Vacations often intentionally include significant thermal discomfort as part of the experience (e.g., sunbathing, and downhill skiing). So people often intentionally make themselves thermally uncomfortable yet the entire foundation of providing the thermal environment in our buildings is done to minimize the percentage of people thermally dissatisfied. We must provide an environment that does not negatively impact short-term health and we need to consider productivity but are our current thermal comfort standards too narrowly defined and do these standards actually contribute to longer-term negative health impacts? This paper examines the possibility that the human body thermoregulatory system has a corollary relationship to the cardiovascular system. It explores the possibility that we have an inherent need to exercise our thermoregulatory system. Potential, physiological, sociological and energy ramifications of these possibilities are discussed.
Date: May 20, 2004
Creator: Stoops, John L.
Partner: UNT Libraries Government Documents Department

Recombination and propagation of quasiparticles in cuprate superconductors

Description: Rapid developments in time-resolved optical spectroscopy have led to renewed interest in the nonequilibrium state of superconductors and other highly correlated electron materials. In these experiments, the nonequilibrium state is prepared by the absorption of short (less than 100 fs) laser pulses, typically in the near-infrared, that perturb the density and energy distribution of quasiparticles. The evolution of the nonequilibrium state is probed by time resolving the changes in the optical response functions of the medium that take place after photoexcitation. Ultimately, the goal of such experiments is to understand not only the nonequilibrium state, but to shed light on the still poorly understood equilibrium properties of these materials. We report nonequilibrium experiments that have revealed aspects of the cup rates that have been inaccessible by other techniques. Namely, the diffusion and recombination coefficients of quasiparticles have been measured in both YBa{sub 2}Cu{sub 3}O{sub 6.5} and Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+x} using time-resolved optical spectroscopy. Dependence of these measurements on doping, temperature and laser intensity is also obtained. To study the recombination of quasiparticles, we measure the change in reflectivity {Delta}R which is directly proportional to the nonequilibrium quasiparticle density created by the laser. From the intensity dependence, we estimate {beta}, the inelastic scattering coefficient and {gamma}{sub th} thermal equilibrium quasiparticle decay rate. We also present the dependence of recombination measurements on doping in Bi{sub 2}Sr{sub 2}CaCu{sub 2}O{sub 8+x}. Going from underdoped to overdoped regime, the sign of {Delta}R changes from positive to negative right at the optimal doping. This is accompanied by a change in dynamics. The decay of {Delta}R stops being intensity dependent exactly at the optimal doping. We provide possible interpretations of these two observations. To study the propagation of quasiparticles, we interfered two laser pulses to introduce a spatially periodic density of quasiparticles. Probing the evolution ...
Date: May 20, 2004
Creator: Gedik, Nuh
Partner: UNT Libraries Government Documents Department

Subcellular proteomic analysis of host-pathogen interactions using human monocytes exposed to Yersinia pestis and Yersinia pseudotuberculosis

Description: Yersinia pestis, the etiological agent of plague, is of concern to human health both from an infectious disease and a civilian biodefense perspective. While Y. pestis and Y. pseudotuberculosis share more than 90% DNA homology, they have significantly different clinical manifestations. Plague is often fatal if untreated, yet Y. pseudotuberculosis causes severe intestinal distress and is rarely fatal. A better understanding of host response to these closely related pathogens may help explain the different mechanisms of virulence and pathogenesis that result in such different clinical outcomes. The aim of this study was to characterize host protein expression changes in human monocyte-like U937 cells after exposure to Y. pestis and Y. pseudotuberculosis. In order to gain global proteomic coverage of host response, proteins from cytoplasmic, nuclear and membrane fractions of host cells were studied by 2-dimensional differential gel electrophoresis (2-D DIGE) and relative protein expression differences were quantitated. Differentially expressed proteins, with at least 1.5 fold expression changes and p values of 0.01 or less, were identified by MALDI-MS or LC/MS/MS. With these criteria, differential expression was detected in 16 human proteins after Y. pestis exposure and 13 human proteins after Y. pseudotuberculosis exposure, of which only two of the differentially expressed proteins identified were shared between the two exposures. Proteins identified in this study are reported to be involved in a wide spectrum of cellular functions and host defense mechanisms including apoptosis, cytoskeletal rearrangement, protein synthesis and degradation, DNA replication and transcription, metabolism, protein folding, and cell signaling. Notably, the differential expression patterns observed can distinguish the two pathogen exposures from each other and from unexposed host cells. The functions of the differentially expressed proteins identified provide insight on the different virulence and pathogenic mechanisms of Y. pestis and Y. pseudotuberculosis.
Date: May 20, 2004
Creator: Zhang, C G; Gonzales, A D; Choi, M W; Chromy, B A; Fitch, J P & McCutchen-Maloney, S L
Partner: UNT Libraries Government Documents Department

The Former Soviet Union and U.S. Foreign Assistance in 1992: The Role of Congress

Description: This report discusses the key role Congress played in formulating an aid program for the former Soviet Union in 1992. Focusing on tensions in the political and legislative system, it delineates congressional achievements — chief of which was the Freedom Support Act. The legislation that was ultimately produced became the basis on which future debate would be conducted regarding how the United States could continue to influence events in the former Soviet Union and assist its transition to an open market economy and democratic institutions.
Date: May 20, 2004
Creator: Tarnoff, Curt
Partner: UNT Libraries Government Documents Department

Rural Housing Service: Agency Has Overestimated Its Rental Assistance Budget Needs over the Life of the Program

Description: A letter report issued by the General Accounting Office with an abstract that begins "The Rural Housing Service's (RHS) Section 521 Rental Assistance Program provides rental subsidies to about 250,000 rural tenants through 5-year contracts with project owners; 20-year contracts were also issued from 1978 through 1982. In early 2003, RHS reported hundreds of millions of dollars in unexpended balances, primarily tied to 5- and 20-year contracts issued from 1978 through 1982. Since contracts remain active until all funds are expired, some of these contracts will likely last as long as 38 years. GAO was asked to assess (1) the activity level of rental assistance contracts issued from 1978 through 1997 that have unexpended balances and the possibility of deobligating these balances, and (2) the activity level of rental assistance contracts issued from 1998 through 2002 and the accuracy of RHS's estimates of the rate at which these funds would be used. The Department of Agriculture commented on our responses to these questions."
Date: May 20, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Financial Management: Audit of the White House Commission on the National Moment of Remembrance for Fiscal Years 2003 and 2002

Description: Correspondence issued by the General Accounting Office with an abstract that begins "The White House Commission on the National Moment of Remembrance (Commission) was created on December 28, 2000, by the National Moment of Remembrance Act (Act). The Commission received appropriated funds in fiscal years 2003 and 2002. Its purpose is to sustain the American spirit through acts of remembrance for those who died serving their country, not only on Memorial Day, but also throughout the year. We are required by the Act to audit the financial transactions of the Commission, and this report covers our work on its fiscal years 2003 and 2002 financial transactions."
Date: May 20, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Debt Ceiling: Analysis of Actions Taken During the 2003 Debt Issuance Suspension Period

Description: A letter report issued by the General Accounting Office with an abstract that begins "GAO is required to review the steps taken by the Department of the Treasury (Treasury) to avoid exceeding the debt ceiling during the 2003 debt issuance suspension period. The committee also directed GAO to determine whether all major accounts that were used for debt ceiling relief have been properly credited or reimbursed. Accordingly, GAO determined whether Treasury followed its normal investment and redemption policies and procedures for the major federal government accounts with investment authority, analyzed the financial aspects of actions Treasury took during this period, and analyzed the impact of policies and procedures Treasury used to manage the debt during the period."
Date: May 20, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Patents: Information about the Publication Provisions of the American Inventors Protection Act

Description: A letter report issued by the General Accounting Office with an abstract that begins "The U.S. Patent and Trademark Office (USPTO) receives over 300,000 patent applications each year. Before the American Inventors Protection Act of 1999, USPTO was required by law to keep the information on patent applications confidential until a patent was granted. The act modified this requirement and mandated that USPTO publish most patent applications 18 months after filing. One exception to this requirement is available to patent applicants filing only in the United States. These applicants can request that their application not be published. The act required GAO to provide information on how patent applications have been affected by the 18-month publication provisions. GAO was required to determine (1) the number of patent applications filed only in the United States, and (2) whether certain differences exist between published and unpublished patent applications. Specifically, GAO examined differences relating to whether the applicant was a large or small entity, the percentage of patents issued by USPTO and applications abandoned by the applicants, and the length of time between filing an application and when USPTO issued a patent or the application was abandoned."
Date: May 20, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

Supplemental Security Income: Sustained Management Attention Needed to Address Residency Violations

Description: Testimony issued by the General Accounting Office with an abstract that begins "The Supplemental Security Income (SSI) program paid about $36 billion in benefits to about 6.9 million recipients in 2003. In recent years, the Social Security Administration (SSA) has identified a general increase in the amount of annual overpayments made to recipients who are not present in the U.S. as required by SSI program guidelines--a problem we refer as "residency violations." This problem has caused concern among both program administrators and policy makers. As such, GAO was asked to determine what is known about the extent to which SSI benefits are improperly paid to individuals who are not present in the United States and to identify any weaknesses in SSA's processes and policies that impede the agency's ability to detect and deter residency violations."
Date: May 20, 2004
Creator: United States. General Accounting Office.
Partner: UNT Libraries Government Documents Department

China and Proliferation of Weapons of Mass Destruction and Missiles: Policy Issues

Description: Congress has long been concerned about whether U.S. policy advances the national interest in reducing the role of the People's Republic of China (PRC) in the proliferation of weapons of mass destruction (WMD) and missiles that could deliver them. China has taken some steps to mollify U.S. concerns about its role in weapons proliferation. Skeptics question whether China's cooperation in weapons nonproliferation has warranted President Bush's pursuit of stronger bilateral ties. This report discusses the national security problem of China's role in weapons proliferation and issues related to the U.S. policy response, including legislation, since the mid-1990s.
Date: May 20, 2004
Creator: Kan, Shirley A.
Partner: UNT Libraries Government Documents Department

An Evaluation of the Difference Formulation for Photon Transport in a Two Level System

Description: In this paper we extend the difference formulation for radiation transport to the case of a single atomic line. We examine the accuracy, performance and stability of the difference formulation within the framework of the Symbolic Implicit Monte Carlo method. The difference formulation, introduced for thermal radiation by some of the authors, has the unique property that the transport equation is written in terms that become small for thick systems. We find that the difference formulation has a significant advantage over the standard formulation for a thick system. The correct treatment of the line profile, however, requires that the difference formulation in the core of the line be mixed with the standard formulation in the wings and this may limit the advantage of the method. We bypass this problem by using the gray approximation. We develop three Monte Carlo solution methods based on different degrees of implicitness for the treatment of the source terms, and we find only conditional stability unless the source terms are treated fully implicitly.
Date: May 20, 2004
Creator: Daffin, F D; McKinley, M S; Brooks, E D & Szoke, A
Partner: UNT Libraries Government Documents Department

Effects of Heavy, Tracked-Vehicle Disturbance on Forest Soil Properties at Fort Benning, Georgia

Description: The purpose of this report is to describe the effects of heavy, tracked-vehicle disturbance on various measures of soil quality in training compartment K-11 at Fort Benning, Georgia. Predisturbance soil sampling in April and October of 2002 indicated statistically significant differences in soil properties between upland and riparian sites. Soil density was less at riparian sites, but riparian soils had significantly greater C and N concentrations and stocks than upland soils. Most of the C stock in riparian soils was associated with mineral-associated organic matter (i.e., the silt + clay fraction physically separated from whole mineral soil). Topographic differences in soil N availability were highly dependent on the time of sampling. Riparian soils had higher concentrations of extractable inorganic N than upland soils and also exhibited significantly greater soil N availability during the spring sampling. The disturbance experiment was performed in May 2003 by driving a D7 bulldozer through the mixed pine/hardwood forest. Post-disturbance sampling was limited to upland sites because training with heavy, tracked vehicles at Fort Benning is generally confined to upland soils. Soil sampling approximately one month after the experiment indicated that effects of the bulldozer were limited primarily to the forest floor (O-horizon) and the surface (0-10 cm) mineral soil. O-horizon dry mass and C stocks were significantly reduced, relative to undisturbed sites, and there was an indication of reduced mineral soil C stocks in the disturbance zone. Differences in the surface (0-10 cm) mineral soil also indicated a significant increase in soil density as a result of disturbance by the bulldozer. Although there was some tendency for greater soil N availability in disturbed soils, the changes were not significantly different from undisturbed controls. It is expected that repeated soil disturbance over time, which will normally occur in a military training area, would simply intensify the ...
Date: May 20, 2004
Creator: Garten, C.T.,JR.
Partner: UNT Libraries Government Documents Department