960 research outputs found

    Comparison of two U.S. power-plant carbon dioxide emissions data sets

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    This paper is not subject to U.S. copyright. The definitive version was published in Environmental Science & Technology 42 (2008): 5688-5693, doi:10.1021/es800221q.Estimates of fossil-fuel CO2 emissions are needed to address a variety of climate-change mitigation concerns over a broad range of spatial and temporal scales. We compared two data sets that report power-plant CO2 emissions in the conterminous U.S. for 2004, the most recent year reported in both data sets. The data sets were obtained from the Department of Energy’s Energy Information Administration (EIA) and the Environmental Protection Agency’s eGRID database. Conterminous U.S. total emissions computed from the data sets differed by 3.5% for total plant emissions (electricity plus useful thermal output) and 2.3% for electricity generation only. These differences are well within previous estimates of uncertainty in annual U.S. fossil-fuel emissions. However, the corresponding average absolute differences between estimates of emissions from individual power plants were much larger, 16.9% and 25.3%, respectively. By statistical analysis, we identified several potential sources of differences between EIA and eGRID estimates for individual plants. Estimates that are based partly or entirely on monitoring of stack gases (reported by eGRID only) differed significantly from estimates based on fuel consumption (as reported by EIA). Differences in accounting methods appear to explain differences in estimates for emissions from electricity generation from combined heat and power plants, and for total and electricity generation emissions from plants that burn nonconventional fuels (e.g., biomass). Our analysis suggests the need for care in utilizing emissions data from individual power plants, and the need for transparency in documenting the accounting and monitoring methods used to estimate emissions.This study was supported by the National Research Program and the Earth System Dynamics Program of the U.S. Geological Survey

    Historical influence of soil and water management on sediment and carbon budgets in the United States

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    This paper is not subject to U.S. copyright. The definitive version was published in Applied Geochemistry 26 (2011): S259, doi:10.1016/j.apgeochem.2011.03.118.The documented history of US soil and water management provides a unique opportunity to examine soil and sediment C storage under conditions of changing management practices. Historical acceleration of erosion due to cultivation has been moderated by improved soil management. Increased construction of dams and locks has expanded areas of aquatic sedimentation in reservoirs and ponds. Enhanced historical sediment deposition rates have been documented in lakes and estuaries. All of these changes have an impact on terrestrial C storage and turnover. The present-day C budget associated with erosion and burial cannot be determined without quantifying the time-dependent changes due to past and present soil and water management

    TRIM5α requires Ube2W to anchor Lys63-linked ubiquitin chains and restrict reverse transcription

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    TRIM5α is an antiviral, cytoplasmic, E3 ubiquitin (Ub) ligase that assembles on incoming retroviral capsids and induces their premature dissociation. It inhibits reverse transcription of the viral genome and can also synthesize unanchored polyubiquitin (polyUb) chains to stimulate innate immune responses. Here, we show that TRIM5α employs the E2 Ub-conjugating enzyme Ube2W to anchor the Lys63-linked polyUb chains in a process of TRIM5α auto-ubiquitination. Chain anchoring is initiated, in cells and in vitro, through Ube2W-catalyzed monoubiquitination of TRIM5α. This modification serves as a substrate for the elongation of anchored Lys63-linked polyUb chains, catalyzed by the heterodimeric E2 enzyme Ube2N/Ube2V2. Ube2W targets multiple TRIM5α internal lysines with Ub especially lysines 45 and 50, rather than modifying the N-terminal amino group, which is instead αN-acetylated in cells. E2 depletion or Ub mutation inhibits TRIM5α ubiquitination in cells and restores restricted viral reverse transcription, but not infection. Our data indicate that the stepwise formation of anchored Lys63-linked polyUb is a critical early step in the TRIM5α restriction mechanism and identify the E2 Ub-conjugating cofactors involved

    The Land Conservation Plan for New Hampshire\u27s Coastal Watershed

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    Spanning 990 square miles and 46 towns, New Hampshire’s coastal watersheds harbor exceptional and irreplaceable natural, cultural, recreational and scenic resources (Figure 1). To advance the long-term protection of these resources, the State of New Hampshire, acting through the NH Coastal Program and the NH Estuaries Project, sought to develop a comprehensive, science-based land conservation plan for our coastal watersheds. The State engaged a partnership of The Nature Conservancy, Society for the Protection of New Hampshire Forests, Rockingham Planning Commission, and Strafford Regional Planning Commission to develop the plan. The New Hampshire Charitable Foundation’s Piscataqua Region supported this effort as a regional approach to setting land conservation priorities and strategies, and provided substantial matching funds. Southeastern New Hampshire is changing before our eyes. The region’s forests, wildlife habitat, clean water, and scenic vistas are increasingly threatened by sprawling development, roads, and other irreversible land use changes. Over the past 36 years, in Rockingham and Strafford Counties, an average of 2,230 acres per year has been converted from undeveloped land to a developed condition. And there is no indication that the pace of development will slow in the foreseeable future. The two Counties are projected to add more than 100,000 new residents from 2000 to 2025, and land values continue to rise steeply. With this conversion comes the loss of important natural resource values provided by undeveloped land, especially for plant and wildlife habitat, clean water, and other “ecological services.” To ensure a healthy environment into the future, it is essential that communities identify, retain, and protect the remaining undeveloped lands and waters that support the most important of these natural resource values and functions. Fortunately, it is not too late to protect the essential natural resources of Great Bay, Hampton Harbor, and the many important watersheds feeding into New Hampshire’s coastline. Thanks to the foresight and dedicated efforts of communities, citizens, conservation organizations and public agencies, more than nine percent of our coastal watersheds are permanently conserved. Many municipalities and communities have embraced land conservation through open space bonds, master plans, and local ordinances. New federal funds, such as the Coastal and Estuarine Land Conservation program, are available for conservation in the coastal watersheds. These protected lands and waters form the basis of a network of conservation areas that will help to safeguard our most critical natural resources over time. Now, more than ever, coastal New Hampshire communities need to ensure that they are making smart, enduring conservation investments in land protection and other effective local and regional strategies to have the greatest and most long-lasting beneficial impact on coastal Now, more than ever, coastal New Hampshire communities need to ensure that they are making smart, enduring conservation investments in land protection and other effective local and regional strategies to have the greatest and most long-lasting beneficial impact on coasta

    The impact of neighbourhood walkability on the effectiveness of a structured education programme to increase objectively measured walking

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    Background: Incorporating physical activity into daily activities is key for the effectiveness of lifestyle education interventions aimed at improving health outcomes; however, consideration of the environmental context in which individuals live is not always made. Walkability is a characteristic of the physical environment, and may be a potential facilitator to changing physical activity levels.  Methods: Using data collected during the Walking Away from Diabetes randomised controlled trial, we examined the association between the walkability of the home neighbourhood and physical activity of participants. We also determined whether home neighbourhood walkability of participants was associated with the intervention effect of the education programme.  Results: Data from 706 participants were available for analysis. Neighbourhood walkability was not significantly associated with any of the physical activity measures at baseline, or at 12, 24 or 36 months following the intervention (p>0.05 for all). There was no association between walkability and change in purposeful steps/ day from baseline to 36months in the usual care or intervention arm; 25.77 (-99.04, 150.58) and 42.97 (-327.63, 413.45) respectively.  Conclusion: Neighbourhood walkability appeared to have no association with objectively-measured physical activity in this population. Furthermore, the walkability of participant’s neighbourhood did not influence the effectiveness of a lifestyle programme

    Development of the Techology for Intermediate Energy Electron Cooling

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    This research was sponsored by the National Science Foundation Grant NSF PHY-931478

    Cancer risk in hospitalised psoriasis patients: a follow-up study in Sweden

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    We examined overall and specific cancer risks among Swedish subjects who had been hospitalised one or more times for psoriasis. A database was created by identifying such patients from the Swedish Hospital Discharge Register and linking them with the Cancer Registry. Follow-up of patients was carried out from the last hospitalisation through 2004. A total of 15 858 patients were hospitalised for psoriasis during 1965–2004, of whom 1408 developed cancer, giving an overall standardised incidence ratios (SIRs) of 1.33. A significant excess was noted for squamous cell skin cancer, and for cancers of the upper aerodigestive tract, oesophagus, stomach, liver, pancreas, lung, kidney and bladder as well as non-Hodgkin lymphoma. Many of these may reflect the effects of alcohol drinking and tobacco smoking. Patients with multiple hospitalisations showed high risk, particularly for oesophageal (SIR 6.97) and skin (SIR 4.76) cancers
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