Science.gov

Sample records for active site finally

  1. Active sites in char gasification: Final technical report

    SciTech Connect

    Wojtowicz, M.; Lilly, W.D.; Perkins, M.T.; Hradil, G.; Calo, J.M.; Suuberg, E.M.

    1987-09-01

    Among the key variables in the design of gasifiers and combustors is the reactivity of the chars which must be gasified or combusted. Significant loss of unburned char is unacceptable in virtually any process; the provision of sufficient residence time for complete conversion is essential. A very wide range of reactivities are observed, depending upon the nature of the char in a process. The current work focuses on furthering the understanding of gasification reactivities of chars. It has been well established that the reactivity of char to gasification generally depends upon three principal factors: (1) the concentration of ''active sites'' in the char; (2) mass transfer within the char; and (3) the type and concentration of catalytic impurities in the char. The present study primarily addresses the first factor. The subject of this research is the origin, nature, and fate of active sites in chars derived from parent hydrocarbons with coal-like structure. The nature and number of the active sites and their reactivity towards oxygen are examined in ''model'' chars derived from phenol-formaldehyde type resins. How the active sites are lost by the process of thermal annealing during heat treatment of chars are studied, and actual rate for the annealing process is derived. Since intrinsic char reactivities are of primary interest in the present study, a fair amount of attention was given to the model char synthesis and handling so that the effect of catalytic impurities and oxygen-containing functional groups in the chemical structure of the material were minimized, if not completely eliminated. The project would not be considered complete without comparing characteristic features of synthetic chars with kinetic behavior exhibited by natural chars, including coal chars.

  2. Supporting State attorneys general CERCLA remedial and enforcement activities at NPL sites. Final report

    SciTech Connect

    Not Available

    1988-06-21

    The directive reaffirms role of State-lead agency for award of cooperative agreements, and states that funds can none-the-less be available to State attorneys general via pass through from the lead agency. Describes the three types of cooperative agreements that can be passed through the State-lead agency to the State Attorney General. The guidance supplements directives no. 9831.6a-6d Interim Final Guidance Package on Funding CERCLA State Enforcement Actions at NPL Sites, dated April 7, 1988.

  3. Risk assessment for the Explosive Washout Lagoons (Site 4), Umatilla Depot Activity Hermiston, Oregon. Final report, Mar 91-Mar 92

    SciTech Connect

    Leinbach, A.; Enright, A.M.; Eaton, W.; Lemont, S.

    1992-03-01

    This document is the Risk Assessment (RA) for the Explosive Washout Lagoons (Site 4) at Umatilla Army Depot Activity (UMDA). The purpose of this RA is to address the potential future health risks posed by explosives-contaminated soil and groundwater associated with Site 4 in the absence of remediation, and to identify safe residual explosives concentrations (remedial action criteria) in soil if remediation is determined to be a requirement. This RA is not intended to address the remediation of contaminated groundwater; contaminated groundwater is addressed only to the extent that contaminants in Site 4 soil are affecting groundwater quality. The potential remediation of contaminated groundwater will be addressed in the installation-wide Baseline RA for UMDA. Based on the available data, explosives contamination appears to be widespread in soil near the lagoons and in groundwater at distances of over 650 yards from the lagoons. Three future land use scenarios-residential, light industrial, and military-and four potential future exposure pathways-soil ingestion, dust inhalation, dermal contact with soil, and groundwater ingestion-were evaluated in the RA to estimate potential future carcinogenic hazards. The results of RA indicate that remediation may be a requirement for soil at Site 4; therefore, remedial action criteria for soil were developed.

  4. Final vegetative cover for closed waste sites

    SciTech Connect

    Cook, J.R.; Salvo, S.K.

    1993-01-22

    Low-level, hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the final closure cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation into and through the waste material. Turf type grasses are currently being used as an interim vegetative cover for most sites. This coverage allows for required monitoring of the closure cap for settlement and maintenance activities. The purpose of this five year study was to evaluate plant materials for use on wastes sites after the post-closure care period that are quickly and easily established and economically maintained, retard water infiltration, provide maximum year-round evapotranspiration, are ecologically acceptable and do not harm the closure cap. The results of the study suggest that two species of bamboo (Phyllostachys (P.) bissetii and P. rubromarginata) can be utilized to provide long lived, low maintenance, climax vegetation for the waste sites after surveillance and maintenance requirements have ceased.

  5. Preliminary site characterization - final report

    SciTech Connect

    Clark, D.; Smith, L.B.

    1993-12-01

    This report summarizes the ecological unit reconnaissance conducted at the F-Area Burning/Rubble Pit(s) RCRA/CERCLA Unit (F-Area BRP) on August 30 and 31, 1993 as part of the RFI/RI baseline risk assessment for the waste unit The baseline risk assessment will assess the potential endangerment to human health and the environment associated with the unit and will be used to evaluate remediation criteria, if needed. The information presented in this report will be used in subsequent stages of the ecological risk assessment to refine the conceptual site model, assist in the selection of contaminants of concern, identify potential ecological receptors, and evaluate trophic relationships and other exposure pathways. The unit reconnaissance survey was conducted in accordance with Specification No. E-18272, Rev. 1 dated August 5, 1993, and the Draft {open_quotes}Ecological Risk Assessment Program Plan for Evaluation of Waste Sites on the Savannah River Site{close_quotes}. The objectives of the site reconnaissance were to: Assess the general characteristics of on-unit biological communities including mammals, birds, reptiles, amphibians, and any aquatic communities present. Determine the location, extent, and characteristics of on-unit ecological resources, such as forested areas and wetlands, that could serve as important wildlife habitat or provide other ecological functions. Identify any overt effects of contamination on biological communities. The field investigations included mapping and describing all wetland and terrestrial habitats; recording wildlife observations of birds, mammals, and reptiles; and investigating ecological resources in nearby downgradient and downstream areas which could be affected by mobile contaminants or future remedial actions. In preparation for the field investigation, existing unit information including aerial photographs and reports were reviewed to help identify and describe ecological resources at the waste unit.

  6. Characterization of the geochemical and physical properties of wetland soils on the Savannah River Site: Field sampling activities. Final report

    SciTech Connect

    Dixon, K.L.

    1992-11-01

    There are 36,000 acres of wetlands on the Savannah River Site (SRS) and an additional 5,000 acres of floodplain. Recent studies of wetland soils near various waste sites at SRS have shown that some wetlands have been contaminated with pollutants resulting from SRS operations. In general, releases of contaminants to wetland areas have been indirect. These releases may have originated at disposal lagoons or waste facilities located in the vicinity of the wetland areas. Transport mechanisms such as surface runoff, soil erosion, sediment transport, and groundwater seepage into downgradient wetland areas are responsible for the indirect discharges to the wetland areas. The SRS determined that a database of background geochemical and physical properties for wetland soils on the SRS was needed to facilitate future remedial investigations, human health and ecological risk assessments, treatability studies, and feasibility studies for the wetland areas. These data are needed for comparison to contaminant data collected from wetland soils that have been affected by contamination from SRS operations. This report describes the efforts associated with the collection of soil cores, preparation of a lithologic log for each core, and the processing and packaging of individual soil samples for shipment to analytical laboratory facilities.

  7. Umatilla Satellite and Release Sites Project : Final Siting Report.

    SciTech Connect

    Montgomery, James M.

    1992-04-01

    This report presents the results of site analysis for the Umatilla Satellite and Release Sites Project. The purpose of this project is to provide engineering services for the siting and conceptual design of satellite and release facilities for the Umatilla Basin hatchery program. The Umatilla Basin hatchery program consists of artificial production facilities for salmon and steelhead to enhance production in the Umatilla River as defined in the Umatilla master plan approved in 1989 by the Northwest Power Planning Council. Facilities identified in the master plan include adult salmon broodstock holding and spawning facilities, facilities for recovery, acclimation, and/or extended rearing of salmon juveniles, and development of river sites for release of hatchery salmon and steelhead. The historic and current distribution of fall chinook, summer chinook, and coho salmon and steelhead trout was summarized for the Umatilla River basin. Current and future production and release objectives were reviewed. Twenty seven sites were evaluated for the potential and development of facilities. Engineering and environmental attributes of the sites were evaluated and compared to facility requirements for water and space. Site screening was conducted to identify the sites with the most potential for facility development. Alternative sites were selected for conceptual design of each facility type. A proposed program for adult holding facilities, final rearing/acclimation, and direct release facilities was developed.

  8. Northeast Oregon Hatchery Project, Final Siting Report.

    SciTech Connect

    Watson, Montgomery

    1995-03-01

    This report presents the results of site analysis for the Bonneville Power Administration Northeast Oregon Hatchery Project. The purpose of this project is to provide engineering services for the siting and conceptual design of hatchery facilities for the Bonneville Power Administration. The hatchery project consists of artificial production facilities for salmon and steelhead to enhance production in three adjacent tributaries to the Columbia River in northeast Oregon: the Grande Ronde, Walla Walla, and Imnaha River drainage basins. Facilities identified in the master plan include adult capture and holding facilities; spawning incubation, and early rearing facilities; full-term rearing facilities; and direct release or acclimation facilities. The evaluation includes consideration of a main production facility for one or more of the basins or several smaller satellite production facilities to be located within major subbasins. The historic and current distribution of spring and fall chinook salmon and steelhead was summarized for the Columbia River tributaries. Current and future production and release objectives were reviewed. Among the three tributaries, forty seven sites were evaluated and compared to facility requirements for water and space. Site screening was conducted to identify the sites with the most potential for facility development. Alternative sites were selected for conceptual design of each facility type. A proposed program for adult holding facilities, final rearing/acclimation, and direct release facilities was developed.

  9. List 9 - Active CERCLIS Sites:

    EPA Pesticide Factsheets

    The List 9 displays the sequence of activities undertaken at active CERCLIS sites. An active site is one at which site assessment, removal, remedial, enforcement, cost recovery, or oversight activities are being planned or conducted.

  10. REVISED FINAL REPORT – INDEPENDENT VERIFICATION SURVEY ACTIVITIES AT THE SEPARATIONS PROCESS RESEARCH UNIT SITES, NISKAYUNA, NEW YORK – DCN 0496-SR-06-1

    SciTech Connect

    Evan Harpenau

    2011-10-10

    The Separations Process Research Unit (SPRU) complex located on the Knolls Atomic Power Laboratory (KAPL) site in Niskayuna, New York, was constructed in the late 1940s to research the chemical separation of plutonium and uranium (Figure A-1). SPRU operated as a laboratory scale research facility between February 1950 and October 1953. The research activities ceased following the successful development of the reduction oxidation and plutonium/uranium extraction processes. The oxidation and extraction processes were subsequently developed for large scale use by the Hanford and Savannah River sites (aRc 2008a). Decommissioning of the SPRU facilities began in October 1953 and continued through the 1990s.

  11. Site 300 Bat Monitoring Final Report

    SciTech Connect

    Drennan, Joe; Tortosa, Justin

    2016-07-18

    From June 15 to 18, 2015, GANDA biologist Graham Neale assisted in programming and fieldtesting of the bat monitoring equipment. The equipment was deployed in the field on a meteorological (MET) tower within Site 300 on June 18, 2015.

  12. ExoMars 2018: the four final candidate Landing Sites

    NASA Astrophysics Data System (ADS)

    Loizeau, Damien; Flahaut, Jessica; Vago, Jorge L.; Hauber, Ernst; Bridges, John C.

    2015-04-01

    December 2014. The Aram Dorsum site comprises Noachian layered sedimentary rocks with a prominent inverted channel system (>80 km long). Potential targets include the inverted channel, the channel margins, a channel transition unit, and pits present within the floodplain. The Hypanis Vallis site lies near two fluvial fan/deltaic systems at the termination of Hypanis and Sabrina Valles. Potential targets include mainly outcrops of expected fine-grained sediments on the smooth transition unit that surrounds the delta/fan, and units around the rim of Magong crater. The Mawrth Vallis site contains one of the largest exposures of phyllosilicates detected on the Martian surface, in Noachian terrain [8]. Potential targets include the mineralogically diverse clay-rich outcrops and ancient channels. The Oxia Planum site lies on Fe/Mg phyllosilicates-rich exposures associated to layered rocks that may be related to the Mawrth Vallis sequence. Potential targets include the clay-rich outcrops as well as channels and inverted channels and delta-fan deposits. New data are being actively acquired by the HiRISE, CRISM and HRSC teams to support the ExoMars 2018 landing site selection process. The ellipses are large and new data are important for characterizing the potential targets and evaluating the safety of the sites. The proposing teams, the ExoMars project team and the LSSWG will continue their analysis and comparison of the sites, aiming to complete the certification of at least one site by September 2016 -- in time for the start of the mission's Critical Design Review (CDR). The final selection of the landing site is expected within 2017. References: [1] http://exploration.esa.int/mars/48088-mission-overview/ [2] http://exploration.esa.int/mars/53462-call-for-exo mars-2018-landing-site-selection/ [3] ExoMars 2018 LSSWG recommendation: http://exploration.esa.int/mars/54707-recommendation-for-the-narrowing-of-exomars-2018-landing-sites/

  13. Final vegetative cover for closed waste sites. Revision 1

    SciTech Connect

    Cook, J.R.; Salvo, S.K.

    1993-01-22

    Low-level, hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the final closure cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation into and through the waste material. Turf type grasses are currently being used as an interim vegetative cover for most sites. This coverage allows for required monitoring of the closure cap for settlement and maintenance activities. The purpose of this five year study was to evaluate plant materials for use on wastes sites after the post-closure care period that are quickly and easily established and economically maintained, retard water infiltration, provide maximum year-round evapotranspiration, are ecologically acceptable and do not harm the closure cap. The results of the study suggest that two species of bamboo (Phyllostachys (P.) bissetii and P. rubromarginata) can be utilized to provide long lived, low maintenance, climax vegetation for the waste sites after surveillance and maintenance requirements have ceased.

  14. Site characterization methodology for aquifers in support of bioreclamation activities. Volume 2: Borehole flowmeter technique, tracer tests, geostatistics and geology. Final report, August 1987-September 1989

    SciTech Connect

    Young, S.C.

    1993-08-01

    This report discusses a field demonstration of a methodology for characterizing an aquifer's geohydrology in the detail required to design an optimum network of wells and/or infiltration galleries for bioreclamation systems. The project work was conducted on a 1-hectare test site at Columbus AFB, Mississippi. The technical report is divided into two volumes. Volume I describes the test site and the well network, the assumptions, and the application of equations that define groundwater flow to a well, the results of three large-scale aquifer tests, and the results of 160 single-pump tests. Volume II describes the bore hole flowmeter tests, the tracer tests, the geological investigations, the geostatistical analysis and the guidelines for using groundwater models to design bioreclamation systems. Site characterization, Hydraulic conductivity, Groundwater flow, Geostatistics, Geohydrology, Monitoring wells.

  15. The role of aeolian sediment in the preservation of archaeological sites in the Colorado River corridor, Grand Canyon, Arizona: final report on research activities, 2003-2006

    USGS Publications Warehouse

    Draut, Amy E.; Rubin, David M.

    2007-01-01

    This report summarizes a three-year study of aeolian sedimentary processes in the Colorado River corridor, Grand Canyon, Arizona, and discusses the relevance of those processes to the preservation of archaeological sites. Findings are based upon detailed sedimentary and geomorphic investigations conducted in three areas of the river corridor, continuous measurements of wind, precipitation, and aeolian sediment transport at six locations for up to 26 months, short-term field study at 35 other sites, examination of historical aerial photographs, and review of data collected and analyzed by previous studies. Detailed results of this study, which involved collaboration with scientists at the Grand Canyon Monitoring and Research Center, National Park Service, Northern Arizona University, the Hopi Tribe, and GeoArch, Inc., have been published previously in topical USGS Open-File Reports (Draut and Rubin, 2005, 2006), a USGS Scientific Investigations Report (Draut and others, 2005), and will be discussed in two forthcoming journal articles. This report serves as an overview of the results and contains new conclusions regarding aeolian sedimentary processes in the Colorado River Ecosystem and their relevance to many archaeological sites.

  16. Umatilla Satellite and Release Sites Project : Final Conceptual Design Report.

    SciTech Connect

    Montgomery, James M.

    1992-03-01

    This report presents the results of site analysis for the Umatilla Satellite and Release Sites Project. The purpose of this project is to provide engineering services for the siting and conceptual design of satellite and release facilities for the Umatilla Basin hatchery program. The Umatilla Basin hatchery program consists of artificial production facilities for salmon and steelhead to enhance production in the Umatilla River as defined in the Umatilla master plan approved in 1989 by the Northwest Power Planning Council. Facilities identified in the master plan include adult salmon broodstock holding and spawning facilities, facilities for recovery, acclimation, and/or extended rearing of salmon juveniles, and development of river sites for release of hatchery salmon and steelhead. The historic and current distribution of fall chinook, summer chinook, and coho salmon and steelhead trout was summarized for the Umatilla River basin. Current and future production and release objectives were reviewed. Twenty seven sites were evaluated for the potential development of facilities. Engineering and environmental attributes of the sites were evaluated and compared to facility requirements for water and space. Site screening was conducted to identify the sites with the most potential for facility development. Alternative sites were selected for conceptual design of each facility type. A proposed program for adult holding facilities, final rearing/acclimation, and direct release facilities was developed.

  17. Salt site performance assessment activities

    SciTech Connect

    Kircher, J.F.; Gupta, S.K.

    1983-01-01

    During this year the first selection of the tools (codes) for performance assessments of potential salt sites have been tentatively selected and documented; the emphasis has shifted from code development to applications. During this period prior to detailed characterization of a salt site, the focus is on bounding calculations, sensitivity and with the data available. The development and application of improved methods for sensitivity and uncertainty analysis is a focus for the coming years activities and the subject of a following paper in these proceedings. Although the assessments to date are preliminary and based on admittedly scant data, the results indicate that suitable salt sites can be identified and repository subsystems designed which will meet the established criteria for protecting the health and safety of the public. 36 references, 5 figures, 2 tables.

  18. Procedures for completion and deletion of National Priorities List Sites (update). Final report

    SciTech Connect

    Not Available

    1989-12-29

    The document focuses on the technical requirements that have been developed to determine the completion of cleanup at Superfund sites and the subsequent procedural requirements for deleting sites from the National Priorities List (NPL). The guidance does not apply to sites that are removed from the NPL so that action can be taken under a different authority or to proposed sites that do not get placed on the final NPL. Expected users of the document include EPA personnel, states, and responsible parties involved in completion of cleanup activities at Superfund sites. The roles and responsibilities of all parties are herein described.

  19. Omaha District Final Cultural Resource Site Monitoring Plan

    DTIC Science & Technology

    2014-06-01

    plan outlines the components and processes of cultural resource site monitoring. The Programmatic Agreement for the Operation and Management of the...Routine Monitoring Plan. Background: In 2004, the Programmatic Agreement for the Operation and Management of the Missouri River Main Stem System for...Compliance with the National Historic Preservation Act, as amended, (March 19, 2004) was finalized. The agreement states; “is an attempt to address

  20. Technical planning activity: Final report

    SciTech Connect

    Not Available

    1987-01-01

    In April 1985, the US Department of Energy's (DOE's) Office of Fusion Energy commissioned the Technical Planning Activity (TPA). The purpose of this activity was to develop a technical planning methodology and prepare technical plans in support of the strategic and policy framework of the Magnetic Fusion Program Plan issued by DOE in February 1985. Although this report represents the views of only the US magnetic fusion community, it is international in scope in the sense that the technical plans contained herein describe the full scope of the tasks that are prerequisites for the commercialization of fusion energy. The TPA has developed a well-structured methodology that includes detailed definitions of technical issues, definitions of program areas and elements, statements of research and development objectives, identification of key decision points and milestones, and descriptions of facility requirements.

  1. Utilities availability report for seven candidate salt sites: Final draft

    SciTech Connect

    Not Available

    1984-12-01

    Stearns Catalytic Corporation (SC) conducted a study of availability and accessibility of electric power and natural gas supplies for each of the seven candidate sites in salt for a nuclear waste repository. The objective of this study is to indicate the existing or potential availability of adequate electric power and natural gas supplies, together with representative routing of reasonable access corridors for utility lines, for the candidate sites at Richton and Cypress Creek Domes in Mississippi, Vacherie Dome in Louisiana, Swisher and Deaf Smith Counties in Texas, and Davis and Lavender Canyons in Utah. The report describes the major characteristics of each supply and the representative routes by which each supply could be connected to the assumed respective repository site. Included are a brief narrative, maps showing representative utilities access routes, and a summary tabulation of relevant data. The supply routes used in this study are not necessarily the recommended, preferred, or selected routes. No decision affecting the final location of the preferred route has been made, therefore the routes used in this study are not to be construed as an implied decision. The routes and supply sources used in this study are for comparative purposes only, as no final selections will be made prior to site characterization.

  2. LANL environmental restoration site ranking system: System description. Final report

    SciTech Connect

    Merkhofer, L.; Kann, A.; Voth, M.

    1992-10-13

    The basic structure of the LANL Environmental Restoration (ER) Site Ranking System and its use are described in this document. A related document, Instructions for Generating Inputs for the LANL ER Site Ranking System, contains detailed descriptions of the methods by which necessary inputs for the system will be generated. LANL has long recognized the need to provide a consistent basis for comparing the risks and other adverse consequences associated with the various waste problems at the Lab. The LANL ER Site Ranking System is being developed to help address this need. The specific purpose of the system is to help improve, defend, and explain prioritization decisions at the Potential Release Site (PRS) and Operable Unit (OU) level. The precise relationship of the Site Ranking System to the planning and overall budget processes is yet to be determined, as the system is still evolving. Generally speaking, the Site Ranking System will be used as a decision aid. That is, the system will be used to aid in the planning and budgetary decision-making process. It will never be used alone to make decisions. Like all models, the system can provide only a partial and approximate accounting of the factors important to budget and planning decisions. Decision makers at LANL will have to consider factors outside of the formal system when making final choices. Some of these other factors are regulatory requirements, DOE policy, and public concern. The main value of the site ranking system, therefore, is not the precise numbers it generates, but rather the general insights it provides.

  3. FINAL CLOSURE PLAN SURFACE IMPOUNDMENTS CLOSURE, SITE 300

    SciTech Connect

    Lane, J E; Scott, J E; Mathews, S E

    2004-09-29

    Lawrence Livermore National Laboratory of the University of California (LLNL) operates two Class II surface impoundments that store wastewater that is discharged from a number of buildings located on the Site 300 Facility (Site 300). The wastewater is the by-product of explosives processing. Reduction in the volume of water discharged from these buildings over the past several years has significantly reduced the wastewater storage needs. In addition, the impoundments were constructed in 1984, and the high-density polyethylene (HDPE) geomembrane liners are nearing the end of their service life. The purpose of this project is to clean close the surface impoundments and provide new wastewater storage using portable, above ground storage tanks at six locations. The tanks will be installed prior to closure of the impoundments and will include heaters for allowing evaporation during relatively cool weather. Golder Associates (Golder) has prepared this Final Closure Plan (Closure Plan) on behalf of LLNL to address construction associated with the clean closure of the impoundments. This Closure Plan complies with State Water Resources Control Board (SWRCB) Section 21400 of the California Code of Regulations Title 27 (27 CCR {section}21400). As required by these regulations and guidance, this Plan provides the following information: (1) A site characterization, including the site location, history, current operations, and geology and hydrogeology; (2) The regulatory requirements relevant to clean closure of the impoundments; (3) The closure procedures; and, (4) The procedures for validation and documentation of clean closure.

  4. Remedial action selection report Maybell, Colorado, site. Final report

    SciTech Connect

    1996-12-01

    The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The site is 2.5 mi (4 km) northeast of the Yampa River on relatively flat terrain broken by low, flat-topped mesas. U.S. Highway 40 runs east-west 2 mi (3.2 km) south of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. The site is situated between Johnson Wash to the east and Rob Pit Mine to the west. Numerous reclaimed and unreclaimed mines are in the immediate vicinity. Aerial photographs (included at the end of this executive summary) show evidence of mining activity around the Maybell site. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [ml]) and contains 2.8 million cubic yards (yd{sup 3}) (2.1 million cubic meters [m{sup 3}]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd 3 (15,000 m{sup 3}) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The volume of off-pile contamination to be placed in the disposal cell is 550,000 yd{sup 3}(420,000 m{sup 3}). The total volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 3.37 million yd{sup 3} (2.58 million m{sup 3}).

  5. Normal Modes Expose Active Sites in Enzymes

    PubMed Central

    Glantz-Gashai, Yitav; Samson, Abraham O.

    2016-01-01

    Accurate prediction of active sites is an important tool in bioinformatics. Here we present an improved structure based technique to expose active sites that is based on large changes of solvent accessibility accompanying normal mode dynamics. The technique which detects EXPOsure of active SITes through normal modEs is named EXPOSITE. The technique is trained using a small 133 enzyme dataset and tested using a large 845 enzyme dataset, both with known active site residues. EXPOSITE is also tested in a benchmark protein ligand dataset (PLD) comprising 48 proteins with and without bound ligands. EXPOSITE is shown to successfully locate the active site in most instances, and is found to be more accurate than other structure-based techniques. Interestingly, in several instances, the active site does not correspond to the largest pocket. EXPOSITE is advantageous due to its high precision and paves the way for structure based prediction of active site in enzymes. PMID:28002427

  6. Site Operator technical report. Final report (1992--1996)

    SciTech Connect

    1996-12-01

    The Southern California Edison Company (SCE) and the US Department of Energy (DOE) entered into cooperative agreement No. DE-FC07-91ID13077 on August 23, 1991, which expired on August 3, 1996. This cooperative agreement provided SCE with DOE cofunding for participation in the DOE`s Electric and Hybrid Vehicle Site Operator Program. In return, SCE provided the DOE with quarterly progress reports which include operating and maintenance data for the electric (EVs) vehicles in SCE`s fleet. Herein is SCE`s final report for the 1992 to 1996 agreement period. As of September 1, 1996 the SCE fleet had 65 electric vehicles in service. A total of 578,200 miles had been logged. During the agreement period, SCE sent the DOE a total of 19 technical reports (Appendix B). This report summarizes the technical achievements which took place during a long, productive and rewarding, relationship with the DOE.

  7. Final audit report of remedial action construction at the UMTRA Project Falls City, Texas, site

    SciTech Connect

    1995-05-01

    This final audit report for the Falls City, Texas, Uranium Mill Tailings Remedial Action Project site summarizes the radiological audits and the quality assurance (QA) in-process surveillances, audits, and final close-out inspection performed by the U.S. Department of Energy (DOE) and Technical Assistance Contractor (TAC). It also summarizes U.S. Nuclear Regulatory Commission (NRC) surveillances. One radiological audit and three radiological surveillances were performed at the Falls City site. These surveillances and audit, which resulted in 31 observations, focused primarily on processing site activities and were performed on the following dates: 3-6 August 1992, 29-30 October 1992, 22-26 March 1993, and 1-3 November 1993. All outstanding radiological issues were closed out at the completion of the construction activities. Six QA in-process surveillances, which resulted in 71 observations, were performed at the Falls City site on the following dates: 22-24 July 1992, 23-25 November 1992, 17-19 May 1993, 16-18 August 1993, 13-15 October 1993, and 2-4 February 1994. All outstanding issues were closed out with the February surveillance on 3 March 1994. The DOE/TAC remedial action close-out inspections of the Falls City site, which resulted in 56 observations, were conducted 9-10 June 1994 and 26 July 1994. The inspections were closed out on 26 January 1995. The NRC performed three on-site construction reviews (OSCR), resulting in seven observations of remedial action construction activities that occurred during site visits. The OSCRs were performed 9 December 1992, 12 May 1993, and 25 October 1993. Since all audit and surveillance observations and recommendations have been closed out, this final audit report segment of the site certification process is complete.

  8. Final covering of the Ronneburg uranium mining site

    SciTech Connect

    Hoepfner, Uwe

    2007-07-01

    The rehabilitation of WISMUT's former Ronneburg uranium mining site involves backfilling of waste rock to the Lichtenberg open pit. The relocation project comprises about 110 million m{sup 3} of sulphide-bearing and AMD-generating waste rock which makes it the most important and most cost-intensive single surface restoration project conducted by WISMUT at the Ronneburg site. The backfilled waste rock has to be covered on an area of about 220 ha to control water infiltration and gas diffusion. Design planning for the final cover placement which began in 2004 had to be based on a comprehensive cost-benefit analysis as well on field tests of alternative cover options which are in compliance with legal requirements. An intensive testing program concerning the vadose zone of soil covers has therefore been started in 2000. The paper presents an overview of the monitoring program and the results of the vadose zone measurements. The water of soil covers have to be predicted for extended evaluation periods. Therefore water balance simulations of single layer covers (storage and evaporation concept) taking current and future soil and climate conditions into account are performed with the HYDRUS 2D code. (author)

  9. Final Reclamation Report: Basalt Waste Isolation Project exploratory shaft site

    SciTech Connect

    Brandt, C.A.; Rickard, W.H. Jr.

    1990-06-01

    The restoration of areas disturbed by activities of the Basalt Waste Isolation Project (BWIP) constitutes a unique operation at the US Department of Energy's (DOE) Hanford Site, both from the standpoint of restoration objectives and the time frame for accomplishing these objectives. The BWIP reclamation program comprises three separate projects: borehole reclamation, Near Surface Test Facility (NSTF) reclamation, and Exploratory Shaft Facility (ESF) reclamation. The main focus of this report is on determining the success of the revegetation effort 1 year after work was completed. This report also provides a brief overview of the ESF reclamation program. 21 refs., 7 figs., 14 tabs.

  10. Final Hanford Site Transuranic (TRU) Waste Characterization QA Project Plan

    SciTech Connect

    GREAGER, T.M.

    2000-12-06

    The Quality Assurance Project Plan (QAPjP) has been prepared for waste characterization activities to be conducted by the Transuranic (TRU) Project at the Hanford Site to meet requirements set forth in the Waste Isolation Pilot Plan (WIPP) Hazardous Waste Facility Permit, 4890139088-TSDF, Attachment B, including Attachments B1 through B6 (WAP) (DOE, 1999a). The QAPjP describes the waste characterization requirements and includes test methods, details of planned waste sampling and analysis, and a description of the waste characterization and verification process. In addition, the QAPjP includes a description of the quality assurance/quality control (QA/QC) requirements for the waste characterization program. Before TRU waste is shipped to the WIPP site by the TRU Project, all applicable requirements of the QAPjP shall be implemented. Additional requirements necessary for transportation to waste disposal at WIPP can be found in the ''Quality Assurance Program Document'' (DOE 1999b) and HNF-2600, ''Hanford Site Transuranic Waste Certification Plan.'' TRU mixed waste contains both TRU radioactive and hazardous components, as defined in the WLPP-WAP. The waste is designated and separately packaged as either contact-handled (CH) or remote-handled (RH), based on the radiological dose rate at the surface of the waste container. RH TRU wastes are not currently shipped to the WIPP facility.

  11. 3D reconstruction of the final PHILAE landing site: Abydos

    NASA Astrophysics Data System (ADS)

    Capanna, Claire; Jorda, Laurent; Lamy, Philippe; Gesquière, Gilles; Delmas, Cédric; Durand, Joëlle; Gaudon, Philippe; Jurado, Eric

    2015-11-01

    The Abydos region is the region of the final landing site of the PHILAE lander. The landing site has been potentially identified on images of this region acquired by the OSIRIS imaging system aboard the orbiter before (Oct 22, 2014) and after (Dec 6-13, 2014) the landing of PHILAE (Lamy et al., in prep.). Assuming that this identification is correct, we reconstructed the topography of Abydos in 3D using a method called ``multiresolution photoclinometry by deformation'' (MPCD, Capanna et al., The Visual Computer, 29(6-8): 825-835, 2013). The method works in two steps: (a) a DTM of this region is extracted from the global MPCD shape model, (b) the resulting triangular mesh is progressively deformed at increasing spatial resolution in order to match a set of 14 images of Abydos at pixel resolutions between 1 and 8 m. The method used to perform the image matching is the L-BFGS-b non-linear optimization (Morales et al., ACM Trans. Math. Softw., 38(1): 1-4, 2011).In spite of the very unfavourable illumination conditions, we achieve a vertical accuracy of about 3 m, while the horizontal sampling is 0.5 m. The accuracy is limited by high incidence angles on the images (about 60 deg on average) combined with a complex topography including numerous cliffs and a few overhangs. We also check the compatibility of the local DTM with the images obtained by the CIVA-P instrument aboard PHILAE. If the Lamy et al. identification is correct, our DTM shows that PHILAE landed in a cavity at the bottom of a small cliff of 8 m height.

  12. Final monitoring plan for site restoration at Murdock, Nebraska.

    SciTech Connect

    LaFreniere, L. M.; Environmental Science Division

    2006-02-28

    environmental impacts of carbon tetrachloride discharge to the surface waters of a tributary creek located immediately north of the town. (3) To permanently reduce carbon tetrachloride concentrations in the groundwater and surface water at Murdock and hence restore these resources for potential beneficial use. To evaluate the effectiveness of the selected remedy and its ability to achieve the objectives specified for this site, monitoring is required. This document outlines the proposed scope of a long-term program for monitoring of the removal action at Murdock. In this section the specific remedial objectives of the action are summarized, and a brief overview of the chosen remedy is provided. Section 2 summarizes the results of a baseline sampling event that documented the distribution of carbon tetrachloride contamination in selected media at the Murdock site immediately before cleanup activities began. Section 3 recommends a strategy for subsequent monitoring of the removal action at Murdock, as well as criteria for evaluating the performance of the remedial systems and the progress of the restoration effort.

  13. Active filter application guide. Final report

    SciTech Connect

    Not Available

    1998-01-01

    Nonlinear loads interacting with a utility can cause harmonic currents and voltages. Nonlinear loads include arcing loads, power converters that use switching devices, and saturable transformers and reactors. When reactive loads interact with harmonic sources, the results can be harmonic distortion, malfunction of harmonic sensitive equipment, and capacitor overload. To solve these harmonic disturbances, most passive harmonic filters must be custom designed to operate with site-specific conditions. Active filters, on the other hand, offer the potential of a single black-box solution that is relatively independent of system parameters. Power quality problems attributable to harmonic voltages and currents are increasing. Traditionally, passive harmonic filters have been used to solve these problems. A more recent approach for harmonic compensation uses active filters. The Active Filter Application Guide covers fundamentals of harmonics, discusses harmonic producing loads, presents harmonic filtering principles (both active and passive), and provides a step-by-step application guide for analyzing and specifying an active filter. Also included in the Guide are two active-filter case studies. Each demonstrates how the application guide can be used to select and specify solutions for both single harmonic load and multiple harmonic producing loads at a clustered site.

  14. Guidance for performing site inspections under CERCLA. Interim report (Final)

    SciTech Connect

    Not Available

    1992-09-01

    The guidance presents EPA's site inspection strategy. The strategy discusses procedural guidelines to investigate potential Superfund (CERCLA) sites for evaluation pursuant to the Hazard Ranking System (HRS), revised in accordance with the Superfund Amendments and Reauthorization Act of 1986. The HRS is the primary means by which EPA evaluates sites for Superfund's National Priorities List (NPL).

  15. Radionuclide site survey report, Melbourne, Florida (RN-72). Final report

    SciTech Connect

    Walker, F.; Lucas, J.; Owen, M.; McKethan, E.M.; MacCartney, J.

    1998-11-16

    The format and content of this report are based on guidance provided by the Preparatory Commission for the CTBT Organization for conducting and documenting radionuclide site surveys (see GTBT/PC/IV/WGB/1) ``Requirements of Site Surveys for Radionuclide Stations``, (30 September 1997). The purpose of this report is to validate that the Melbourne site will fulfill the requirements for treaty compliance.

  16. Final report : site reclassification investigation for Courtland, Kansas.

    SciTech Connect

    LaFreniere, L. M.; Dennis, C. B.; Environmental Science Division

    2006-01-31

    The Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), formerly operated a grain storage facility in Courtland, Kansas. Prior to 1986, commercial grain fumigants containing carbon tetrachloride were commonly used by the CCC/USDA and the grain industry to preserve stored grain. In 1999, the Kansas Department of Health and Environment (KDHE) identified the former CCC/USDA operation as the likely source of carbon tetrachloride found in groundwater east of the former CCC/USDA facility in Courtland. Sampling by the KDHE in April 1998 had found carbon tetrachloride in the Garman residence lawn and garden well at a concentration of 2.1 {micro}g/L and in the Hoard residence lawn and garden well at a concentration of 0.5 {micro}g/L. Subsequent soil and groundwater sampling by the KDHE at the former CCC/USDA facility found no indication of a continuing source, and subsequent sampling of the affected wells showed generally declining contaminant levels. At the request of the KDHE and the CCC/USDA, Argonne National Laboratory prepared a Work Plan for Groundwater Sampling for Potential Site Reclassification, Courtland, Kansas (Argonne 2004). The objective of the proposed work was to conduct a single groundwater monitoring event and collect information necessary to update the status of the previously detected groundwater contamination, in support of an evaluation of appropriate actions for reclassification of the status of this site from active to resolved, under the Intergovernmental Agreement between the KDHE and the USDA's Farm Service Agency (FSA). The reclassification would be in accordance with the KDHE's Reclassification Plan (Policy No. BERRS-024, online at http://www.kdhe.state.ks.us/pdf/ber/scp/reclass.pdf). The KDHE approved the Work Plan on August 8, 2005. Sampling was conducted on September 7, 2005.

  17. Atmospheric Line of Site Experiment (ALOSE) Final Campaign Summary

    SciTech Connect

    Smith, W.; Green, S.; Howard, M.; Yesalusky, M.; Modlin, N.

    2016-03-01

    The Atmospheric Line of Site Experiment (ALOSE) was a project to produce best-estimate atmospheric state measurements at the: 1. DOE Atmospheric Radiation Measurement (ARM) Clouds and Radiation Test-bed (CART) site located in Lamont, Oklahoma (11–14 December 2012) 2. Poker Flat Alaska Research Range (PFRR) located in Poker Flat, Alaska (19–26 February 2013) 3. DOE ARM CART site located in Lamont, Oklahoma (24–28 April 2013) 4. DOE ARM CART site located in Lamont, Oklahoma (9–15 July 2013) 5. DOE ARM Tropical Western Pacific (TWP) site located in Darwin, Australia (27 September–3 October 2013).

  18. Near-Site Transportation Infrastructure Project. Final report

    SciTech Connect

    Viebrock, J.M.; Mote, N.

    1992-02-01

    There are 122 commercial nuclear facilities from which spent nuclear fuel will be accepted by the Federal Waste Management System (FWMS). Since some facilities share common sites and some facilities are on adjacent sites, 76 sites were identified for the Near-Site Transportation Infrastructure (NSTI) project. The objective of the NSTI project was to identify the options available for transportation of spent-fuel casks from each of these commercial nuclear facility sites to the main transportation routes -- interstate highways, commercial rail lines and navigable waterways available for commercial use. The near-site transportation infrastructure from each site was assessed, based on observation of technical features identified during a survey of the routes and facilities plus data collected from referenced information sources. The potential for refurbishment of transportation facilities which are not currently operational was also assessed, as was the potential for establishing new transportation facilities.

  19. Final work plan : environmental site investigation at Sylvan Grove, Kansas.

    SciTech Connect

    LaFreniere, L. M.

    2012-07-15

    what future CCC/USDA actions may be necessary, with the ultimate goal of achieving classification of the Sylvan Grove site at no further action status. The proposed activities are to be performed on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory, a nonprofit, multidisciplinary research center operated by the UChicago Argonne, LLC, for the U.S. Department of Energy. Argonne provides technical assistance to the CCC/USDA concerning environmental site characterization and remediation at former grain storage facilities. Argonne issued a Master Work Plan (Argonne 2002) that has been approved by the KDHE. The Master Work Plan describes the general scope of all investigations at former CCC/USDA facilities in Kansas and provides guidance for these investigations. That document should be consulted for the complete details of plans for work associated with the former CCC/USDA facility at Sylvan Grove.

  20. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2010 CFR

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The...

  1. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ... 40 Protection of Environment 26 2013-07-01 2013-07-01 false Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The...

  2. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2011 CFR

    2011-07-01

    ... 40 Protection of Environment 25 2011-07-01 2011-07-01 false Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The...

  3. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 26 2012-07-01 2011-07-01 true Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The...

  4. 40 CFR 228.15 - Dumping sites designated on a final basis.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 25 2014-07-01 2014-07-01 false Dumping sites designated on a final basis. 228.15 Section 228.15 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY (CONTINUED) OCEAN DUMPING CRITERIA FOR THE MANAGEMENT OF DISPOSAL SITES FOR OCEAN DUMPING § 228.15 Dumping sites designated on a final basis. (a)(1) The...

  5. Siting guidelines for utility application of wind turbines. Final report

    SciTech Connect

    Pennell, W.T.

    1983-01-01

    Utility-oriented guidelines are described for identifying viable sites for wind turbines. Topics and procedures are also discussed that are important in carrying out a wind turbine siting program. These topics include: a description of the Department of Energy wind resource atlases; procedures for predicting wind turbine performance at potential sites; methods for analyzing wind turbine economics; procedures for estimating installation and maintenance costs; methods for anlayzing the distribution of wind resources over an area; and instrumentation for documenting wind behavior at potential sites. The procedure described is applicable to small and large utilities. Although the procedure was developed as a site-selection tool, it can also be used by a utility who wishes to estimate the potential for wind turbine penetration into its future generation mix.

  6. Validated ligand mapping of ACE active site

    NASA Astrophysics Data System (ADS)

    Kuster, Daniel J.; Marshall, Garland R.

    2005-08-01

    Crystal structures of angiotensin-converting enzyme (ACE) complexed with three inhibitors (lisinopril, captopril, enalapril) provided experimental data for testing the validity of a prior active site model predicting the bound conformation of the inhibitors. The ACE active site model - predicted over 18 years ago using a series of potent ACE inhibitors of diverse chemical structure - was recreated using published data and commercial software. Comparison between the predicted structures of the three inhibitors bound to the active site of ACE and those determined experimentally yielded root mean square deviation (RMSD) values of 0.43-0.81 Å, among the distances defining the active site map. The bound conformations of the chemically relevant atoms were accurately deduced from the geometry of ligands, applying the assumption that the geometry of the active site groups responsible for binding and catalysis of amide hydrolysis was constrained. The mapping of bound inhibitors at the ACE active site was validated for known experimental compounds, so that the constrained conformational search methodology may be applied with confidence when no experimentally determined structure of the enzyme yet exists, but potent, diverse inhibitors are available.

  7. Final Hanford Site Transuranic (TRU) Waste Characterization QA Project Plan

    SciTech Connect

    GREAGER, T.M.

    1999-09-09

    The Transuranic Waste Characterization Quality Assurance Program Plan required each US Department of Energy (DOE) site that characterizes transuranic waste to be sent the Waste Isolation Pilot Plan that addresses applicable requirements specified in the QAPP.

  8. Guidance document for preparing water sampling and analysis plans for UMTRA sites. Final [report

    SciTech Connect

    Not Available

    1993-09-01

    A water sampling and analysis plan (WSAP) is required for each Uranium Mill Tailings Remedial Action (UMTRA) site to provide rationale for groundwater and surface water sampling at disposal sites and former processing sites. The WSAP identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequencies for the groundwater and surface water monitoring stations at each site. Section 2.0 of this WSAP Guidance Document describes the WSAP format. Sections 3.0 and 4.0 provide guidance for selecting sampling frequencies and sampling locations, respectively. Section 5.0 contains criteria for selecting analytical parameters. Section 6.0 provides guidance for the contents of each site`s WSAP file. Finally, Section 7.0 presents the references used to prepare this document. The purpose of this guidance document is to provide a consistent technical approach for sampling and monitoring activities performed under WSAPs and a consistent format for WSAP documents. This document is designed for use by the Technical Assistance Contractor (TAC) to prepare WSAPs and by the US Department of Energy (DOE), Nuclear Regulatory Commission, state and tribal agencies, regulatory agencies, and the public to evaluate the contents of the WSAPS. This guidance document may be updated periodically based on new or changing regulations.

  9. Final audit report of remedial action construction at the UMTRA Project, Grand Junction, Colorado, processing site

    SciTech Connect

    1995-02-01

    This final audit report (FAR) for remedial action at the Grand Junction, Colorado, Uranium Mill Tailings Remedial Action (UMTRA) Project processing site consists of a summary of the radiological surveillances/ audits, the quality assurance (QA) in-process surveillances, and the QA final close-out inspection performed by the US Department of Energy (DOE) and Technical Assistance Contractor (TAC). The FAR also summarizes other surveillances performed by the US Nuclear Regulatory Commission (NRC). To summarize, a total of one finding and 127 observations were noted during DOE/TAC audit and surveillance activities. The NRC noted general site-related observations during the OSCRs. Follow-up to responses required from MK-Ferguson for the DOE/TAC finding and observations indicated that all issues related to the Grand Junction processing site were resolved and closed out to the DOE`s satisfaction. The NRC OSCRs resulted in no issues related to the Grand Junction processing site requiring a response from MK-Ferguson.

  10. Final audit report of remedial action construction at the UMTRA Project Ambrosia Lake, New Mexico, site

    SciTech Connect

    1995-09-01

    The final audit report for remedial action at the Ambrosia Lake, New Mexico, Uranium Mill Tailings Remedial Action (UMTRA) Project site consists of a summary of the radiological surveillances/audits, quality assurance (QA) in-process surveillances, and a QA final closeout inspection performed by the US Department of Energy (DOE) and the Technical Assistance Contractor (TAC). One radiological surveillance and three radiological audits were performed at the Ambrosia Lake site. The surveillance was performed on 12--16 April 1993 (DOE, 1993d). The audits were performed on 26--29 July 1993 (DOE, 1993b); 21--23 March 1994 (DOE, 1994d); and 1--2 August 1994 (DOE, 1994d). The surveillance and audits resulted in 47 observations. Twelve of the observations raised DOE concerns that were resolved on site or through subsequent corrective action. All outstanding issues were satisfactorily closed out on 28 December 1994. The radiological surveillance and audits are discussed in this report. A total of seven QA in-process surveillances were performed at the Ambrosia Lake UMTRA site are discussed. The DOE/TAC Ambrosia Lake final remedial action close-out inspection was conducted on 26 July 1995 (DOE, 1995a). To summarize, a total of 155 observations were noted during DOE/TAC audit and surveillance activities. Follow-up to responses required from the RAC for the DOE/TAC surveillance and audit observations indicated that all issues related to the Ambrosia Lake site were resolved and closed to the satisfaction of the DOE.

  11. Energy conserving site design case study: Shenandoah, Georgia. Final report

    SciTech Connect

    Not Available

    1980-01-01

    The case study examines the means by which energy conservation can be achieved at an aggregate community level by using proper planning and analytical techniques for a new town, Shenandoah, Georgia, located twenty-five miles southwest of Atlanta's Hartsfield International Airport. A potentially implementable energy conservation community plan is achieved by a study team examining the land use options, siting characteristics of each building type, alternate infrastructure plans, possible decentralized energy options, and central utility schemes to determine how community energy conservation can be achieved by use of pre-construction planning. The concept for the development of mixed land uses as a passively sited, energy conserving community is based on a plan (Level 1 Plan) that uses the natural site characteristics, maximizes on passive energy siting requirement, and allows flexibility for the changing needs of the developers. The Level 2 Plan is identical with Level 1 plan plus a series of decentraized systems that have been added to the residential units: the single-family detached, the apartments, and the townhouses. Level 3 Plan is similar to the Level 1 Plan except that higher density dwellings have been moved to areas adjacent to central site. The total energy savings for each plan relative to the conventional plan are indicated. (MCW)

  12. Final Hanford Site Transuranic (TRU) Waste Characterization QA Project Plan

    SciTech Connect

    GREAGER, T.M.

    1999-12-14

    The Transuranic Waste Characterization Quality Assurance Program Plan required each U.S. Department of Energy (DOE) site that characterizes transuranic waste to be sent the Waste Isolation Pilot Plan that addresses applicable requirements specified in the quality assurance project plan (QAPP).

  13. Industrial Sites Project Establishment of Final Action Levels, Rev. No.: 0

    SciTech Connect

    Boehlecke, Robert F.

    2006-02-01

    The U.S. Department of Energy, National Nuclear Security Administration Nevada Site Office (NNSA/NSO) oversees numerous sites on the Nevada Test Site (NTS) and other locations in the State of Nevada that have been impacted by activities related to the development and testing of nuclear devices and by other activities. NNSA/NSO is responsible for protecting members of the public, including site workers, from harmful exposure to both chemical and radiological contaminants at these sites as they remediate these sites. The Nevada Division of Environmental Protection (NDEP) is the primary state agency responsible for protection of human health and the environment with respect to chemical and radiological wastes. In 1996 the DOE, U.S. Department of Defense, and the State of Nevada entered into an agreement known as the ''Federal Facility Agreement and Consent Order'' (FFACO) (1996). Appendix VI to the FFACO describes the strategy employed to plan, implement, and complete environmental corrective action activities at NTS and other locations in the state of Nevada. One of the categories of corrective action units (CAUs) is Industrial Sites, which consists of approximately 1,150 locations that may require some level of investigation and corrective action. To evaluate the need for the extent of corrective action at a particular site, NNSA/NSO assesses the potential impacts to receptors by comparing measurements of contaminant concentrations to risk-based (chemical) and dose-based (radionuclide) standards (action levels). Preliminary action levels (PALs) are established as part of the data quality objective (DQO) process, and are presented in one or more FFACO documents generated as part of the corrective action process. This document formally defines and clarifies the NDEP-approved process NNSA/NSO Industrial Sites Project uses to fulfill the requirements of the FFACO and state regulations. This process establishes final action levels (FALs) based on the risk

  14. Seismic Surface-Wave Tomography of Waste Sites - Final Report

    SciTech Connect

    Long, Timothy L.

    2000-09-14

    The objective of this study was to develop analysis programs for surface-wave group-velocity tomography, and apply these to three test areas. We succeeded by obtaining data covering two square areas that were 30 meters on a side, and a third area that was 16 meters on a side, in addition to a collaborative effort wherein we processed data from the Oak Ridge National Laboratory site. At all sites, usable group velocities were obtained for frequencies from 16 to 50 Hz using a sledgehammer source. The resulting tomographic images and velocity anomalies were sufficient to delineate suspected burial trenches (one 4-meters deep) and anomalous velocity structure related to rocks and disturbed soil. The success was not uniform because in portions of one area the inversion for shear-wave structure became unstable. More research is needed to establish a more robust inversion technique.

  15. Nevada Test Site tortoise population monitoring study. Final report

    SciTech Connect

    Mueller, J.M.; Zander, K.K.

    1994-12-01

    A Tortoise Population Monitoring Study was initiated to determine and monitor the density of desert tortoises (Gopherus agassizii) on the Nevada Test Site. Quadrat sampling was conducted following methodology described in the Draft Desert Tortoise Recovery Plan (FWS, 1993). So few tortoises were found that densities could not be calculated. Based on estimates of capture probabilities and densities from other studies, it was determined that 1-km{sup 2} (0.4 mi{sup 2}) plots did not contain enough tortoises for estimating densities with the Recovery Plan methods. It was recommended that additional surveys on the Nevada Test Site using those methods not be conducted. Any future efforts to monitor desert tortoise densities should start by identifying other possible methods, determining their relative power to detect changes, and estimating their cost.

  16. Cleanup of the Western Research Institute North Site. Final report

    SciTech Connect

    Merriam, N.W.

    1996-09-01

    The objective of this project is to clean up the Western Research Institute`s North Site in an environmentally sound and cost-effective manner. Work is broken down into the following phases: Phase 1, definition of waste streams; Phase 2, disposal of hazardous wastes; Phase 3, disposal of nonhazardous materials; Phase 4, soil sampling and disposal of buried wastes; Phase 5, decontamination and disposal of equipment; Phase 5a, groundwater monitoring; and Phase 6, preparation of material inventory database.

  17. [Paleoclimatology studies for Yucca Mountain site characterization]. Final report

    SciTech Connect

    1996-05-03

    This report consists of two separate papers: Fernley Basin studies; and Influence of sediment supply and climate change on late Quaternary eolian accumulation patterns in the Mojave Desert. The first study involved geologic mapping of late Quaternary sediments and lacustrine features combined with precise control of elevations and descriptions of sediments for each of the major sedimentary units. The second paper documents the response of a major eolian sediment transport system in the east-central Mojave Desert: that which feeds the Kelso Dune field. Information from geomorphic, stratigraphic, and sedimentologic studies of eolian deposits and landforms is combined with luminescence dating of these deposits to develop a chronology of periods of eolian deposition. Both studies are related to site characterization studies of Yucca Mountain and the forecasting of rainfall patterns possible for the high-level radioactive waste repository lifetime.

  18. Hydrogeological-Geophysical Methods for Subsurface Site Characterization - Final Report

    SciTech Connect

    Rubin, Yoram

    2001-01-01

    The goal of this research project is to increase water savings and show better ecological control of natural vegetation by developing hydrogeological-geophysical methods for characterizing the permeability and content of water in soil. The ground penetrating radar (GPR) tool was developed and used as the surface geophysical method for monitoring water content. Initial results using the tool suggest that surface GPR is a viable technique for obtaining precision volumetric water content profile estimates, and that laboratory-derived petrophysical relationships could be applied to field-scale GPR data. A field-scale bacterial transport study was conducted within an uncontaminated sandy Pleistocene aquifer to evaluate the importance of heterogeneity in controlling the transport of bacteria. Geochemical, hydrological, geological, and geophysical data were collected to characterize the site prior to and after chemical and bacterial injection experiments. Study results shows that, even within the fairly uniform shallow marine deposits of the narrow channel focus area, heterogeneity existed that influenced the chemical tracer transport over lateral distances of a few meters and vertical distances of less than a half meter. The interpretation of data suggest that the incorporation of geophysical data with limited hydrological data may provide valuable information about the stratigraphy, log conductivity values, and the spatial correlation structure of log conductivity, which have traditionally been obtainable only by performing extensive and intrusive hydrological sampling.

  19. Final report : Hanover environmental site investigation, 2009-2010.

    SciTech Connect

    LaFreniere, L. M.

    2011-06-07

    associated with potential exposure to contaminated groundwater at Hanover. No drinking water wells are known to exist in Hanover, and the drinking water supply comes from RWD No.1 at Lanham, Kansas, located 6.5 mi north of Hanover. Limited potential risk was identified due to exposure to indoor air contaminated with carbon tetrachloride, but this risk has been mitigated, thereby removing this threat to human health. Radon is prevalent in the community, at concentrations exceeding the level at which the EPA recommends additional measures (testing and/or mitigation). The recommended testing and mitigation (if needed) are the responsibility of the homeowners. In the current condition in which no private wells are used for drinking water in the affected area, no unacceptable human health risk from carbon tetrachloride is associated with the identified impacted media at the Hanover site.

  20. Assessing Risks to Populations at Superfund and Rcra Sites: Characterizing Effects on Populations (Final)

    EPA Science Inventory

    The Ecological Risk Assessment Support Center (ERASC) announced the release of the final document titled, Assessing Risks to Populations at Superfund and RCRA Sites: Characterizing Effects on Populations.

  1. Partial Updating of TSCA Inventory DataBase; Production and Site Reports; Final Rule

    EPA Pesticide Factsheets

    A partial updating of the TSCA inventory database. The final rule requires manufacturers and importers of certain chemical substances included on the TSCA Chemical Substances Inventory to report current data on the production volume, plant site, etc.

  2. Final agreement to study contamination at Smurfit Stone Mill site (Missoula County, Mont.)

    EPA Pesticide Factsheets

    (Denver, Colo. - November 12, 2015) The U.S. Environmental Protection Agency (EPA) has announced a final agreement to investigate contamination at the Smurfit Stone Mill Superfund site, in Missoula County, Montana. Under the terms of the agreement, M

  3. Final audit report of remedial action construction at the UMTRA Project Mexican Hat, Utah -- Monument Valley, Arizona, sites

    SciTech Connect

    1995-10-01

    The final audit report for remedial action at the Mexican Hat, Utah, Monument Valley, Arizona, Uranium Mill Tailings Remedial Action (UMTRA) Project sites consists of a summary of the radiological surveillances/audits, quality assurance (QA) in-process surveillances, and QA remedial action close-out inspections performed by the US Department of Energy (DOE) and the Technical Assistance Contractor (TAC); on-site construction reviews (OSCR) performed by the US Nuclear Regulatory Commission (NRC); and a surveillance performed by the Navajo Nation. This report refers to remedial action activities performed at the Mexican Hat, Utah--Monument Valley, Arizona, Uranium Mill Tailings Remedial Action (UMTRA) Project sites.

  4. Active and regulatory sites of cytosolic 5'-nucleotidase.

    PubMed

    Pesi, Rossana; Allegrini, Simone; Careddu, Maria Giovanna; Filoni, Daniela Nicole; Camici, Marcella; Tozzi, Maria Grazia

    2010-12-01

    Cytosolic 5'-nucleotidase (cN-II), which acts preferentially on 6-hydroxypurine nucleotides, is essential for the survival of several cell types. cN-II catalyses both the hydrolysis of nucleotides and transfer of their phosphate moiety to a nucleoside acceptor through formation of a covalent phospho-intermediate. Both activities are regulated by a number of phosphorylated compounds, such as diadenosine tetraphosphate (Ap₄A), ADP, ATP, 2,3-bisphosphoglycerate (BPG) and phosphate. On the basis of a partial crystal structure of cN-II, we mutated two residues located in the active site, Y55 and T56. We ascertained that the ability to catalyse the transfer of phosphate depends on the presence of a bulky residue in the active site very close to the aspartate residue that forms the covalent phospho-intermediate. The molecular model indicates two possible sites at which adenylic compounds may interact. We mutated three residues that mediate interaction in the first activation site (R144, N154, I152) and three in the second (F127, M436 and H428), and found that Ap₄A and ADP interact with the same site, but the sites for ATP and BPG remain uncertain. The structural model indicates that cN-II is a homotetrameric protein that results from interaction through a specific interface B of two identical dimers that have arisen from interaction of two identical subunits through interface A. Point mutations in the two interfaces and gel-filtration experiments indicated that the dimer is the smallest active oligomerization state. Finally, gel-filtration and light-scattering experiments demonstrated that the native enzyme exists as a tetramer, and no further oligomerization is required for enzyme activation.

  5. Corrosion Research And Web Site Activities

    NASA Technical Reports Server (NTRS)

    Heidersbach, Robert H.

    2001-01-01

    This report covers corrosion-related activities at the NASA Kennedy Space Center during the summer of 2000. The NASA Kennedy Space Center's corrosion web site, corrosion.ksc.nasa.gov, was updated with new information based on feedback over the past two years. The methodology for a two-year atmospheric exposure testing program to study the effectiveness of commercial chemicals sold for rinsing aircraft and other equipment was developed and some preliminary laboratory chemical analyses are presented.

  6. Corrosion Research and Web Site Activities

    NASA Technical Reports Server (NTRS)

    Heidersbach, Robert H.

    2002-01-01

    This report covers corrosion-related activities at the NASA Kennedy Space Center during the summer of 2000. The NASA Kennedy Space Center's corrosion web site, corrosion.ksc.nasa.gov, was updated with new information based on feedback over the past two years. The methodology for a two-year atmospheric exposure testing program to study the effectiveness of commercial chemicals sold for rinsing aircraft and other equipment was developed and some preliminary laboratory chemical analyses are presented.

  7. 10 CFR 52.83 - Finality of referenced NRC approvals; partial initial decision on site suitability.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... 10 Energy 2 2013-01-01 2013-01-01 false Finality of referenced NRC approvals; partial initial decision on site suitability. 52.83 Section 52.83 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.83 Finality of referenced...

  8. 10 CFR 52.83 - Finality of referenced NRC approvals; partial initial decision on site suitability.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... 10 Energy 2 2012-01-01 2012-01-01 false Finality of referenced NRC approvals; partial initial decision on site suitability. 52.83 Section 52.83 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.83 Finality of referenced...

  9. 10 CFR 52.83 - Finality of referenced NRC approvals; partial initial decision on site suitability.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... 10 Energy 2 2010-01-01 2010-01-01 false Finality of referenced NRC approvals; partial initial decision on site suitability. 52.83 Section 52.83 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.83 Finality of referenced...

  10. 10 CFR 52.83 - Finality of referenced NRC approvals; partial initial decision on site suitability.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... 10 Energy 2 2014-01-01 2014-01-01 false Finality of referenced NRC approvals; partial initial decision on site suitability. 52.83 Section 52.83 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.83 Finality of referenced...

  11. 10 CFR 52.83 - Finality of referenced NRC approvals; partial initial decision on site suitability.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... 10 Energy 2 2011-01-01 2011-01-01 false Finality of referenced NRC approvals; partial initial decision on site suitability. 52.83 Section 52.83 Energy NUCLEAR REGULATORY COMMISSION (CONTINUED) LICENSES, CERTIFICATIONS, AND APPROVALS FOR NUCLEAR POWER PLANTS Combined Licenses § 52.83 Finality of referenced...

  12. 81 FR 43631 - Final Supplementary Rules for the Cove Recreation Site, Owyhee County, Idaho

    Federal Register 2010, 2011, 2012, 2013, 2014

    2016-07-05

    ....HT0000 LXSS020D0000 241A 4500076900] Final Supplementary Rules for the Cove Recreation Site, Owyhee... Snake River Birds of Prey National Conservation Area (NCA) in Owyhee County, Idaho. These final...). Originally, public comments were due August 25, 2014. The BLM accepted comments from the Owyhee...

  13. 10 CFR 52.39 - Finality of early site permit determinations.

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... NUCLEAR POWER PLANTS Early Site Permits § 52.39 Finality of early site permit determinations. (a... nuclear power plant, the Commission shall treat as resolved changes that are equivalent to those that... approved an emergency plan (or major features thereof) that is in use by a licensee of a nuclear...

  14. 10 CFR 52.39 - Finality of early site permit determinations.

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... NUCLEAR POWER PLANTS Early Site Permits § 52.39 Finality of early site permit determinations. (a... nuclear power plant, the Commission shall treat as resolved changes that are equivalent to those that... approved an emergency plan (or major features thereof) that is in use by a licensee of a nuclear...

  15. 10 CFR 52.39 - Finality of early site permit determinations.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... NUCLEAR POWER PLANTS Early Site Permits § 52.39 Finality of early site permit determinations. (a... nuclear power plant, the Commission shall treat as resolved changes that are equivalent to those that... approved an emergency plan (or major features thereof) that is in use by a licensee of a nuclear...

  16. Stressor Identification (Si) at Contaminated Sites: Upper Arkansas River, Colorado (Final)

    EPA Science Inventory

    EPA announced the availability of the final report, Stressor Identification (SI) at Contaminated Sites: Upper Arkansas River, Colorado. This report describes a causal assessment for impairments of plant growth and plant species richness at a terrestrial contaminated site ...

  17. EPA Finalizes Plan to Address Pollution at San German, Puerto Rico Toxic Site

    EPA Pesticide Factsheets

    (New York, N.Y.) The U.S. Environmental Protection Agency has finalized a plan to address contaminated soil and groundwater at the San German Groundwater Contamination Superfund Site in San German, Puerto Rico. The site includes the Retiro Industrial Park,

  18. Active Sites Environmental Monitoring Program: Program plan

    SciTech Connect

    Ashwood, T.L.; Wickliff, D.S.; Morrissey, C.M.

    1992-02-01

    The Active Sites Environmental Monitoring Program (ASEMP), initiated in 1989, provides early detection and performance monitoring of transuranic (TRU) waste and active low-level waste (LLW) facilities at Oak Ridge National Laboratory (ORNL) in accordance with US Department of Energy (DOE) Order 5820.2A. Active LLW facilities in Solid Waste Storage Area (SWSA) 6 include Tumulus I and Tumulus II, the Interim Waste Management Facility (IWMF), LLW silos, high-range wells, asbestos silos, and fissile wells. The tumulus pads and IWMF are aboveground, high-strength concrete pads on which concrete vaults containing metal boxes of LLW are placed; the void space between the boxes and vaults is filled with grout. Eventually, these pads and vaults will be covered by an engineered multilayered cap. All other LLW facilities in SWSA 6 are below ground. In addition, this plan includes monitoring of the Hillcut Disposal Test Facility (HDTF) in SWSA 6, even though this facility was completed prior to the data of the DOE order. In SWSA 5 North, the TRU facilities include below-grade engineered caves, high-range wells, and unlined trenches. All samples from SWSA 6 are screened for alpha and beta activity, counted for gamma-emitting isotopes, and analyzed for tritium. In addition to these analytes, samples from SWSA 5 North are analyzed for specific transuranic elements.

  19. Selection and cultivation of final vegetative cover for closed waste sites at the Savannah River Site, SC

    SciTech Connect

    Cook, J.R.; Salvo, S.K.

    1992-12-31

    Low-level, hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the final closure cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation into and through the waste material. Turf type grasses are currently being used as a vegetative cover for most sites. Consequently, the sites require periodic mowing and other expensive annual maintenance practices. The purpose of this five year study was to evaluate alternative plant material for use on wastes sites that is quickly and easily established and economically maintained, retards water infiltration, provides maximum year-round evapotranspiration, is ecologically acceptable and does not harm the closure cap. The results of the study are described in this report and suggest that two species of bamboo (Phyllostachys bissetii and P. rubromarainata) can be utilized to provide long lived, low maintenance, climax vegetation for the waste sites. These large species of bamboo will also reduce the probability of intrusion by humans, animals and deeply rooted plant species.

  20. Selection and cultivation of final vegetative cover for closed waste sites at the Savannah River Site, SC

    SciTech Connect

    Cook, J.R. ); Salvo, S.K. )

    1992-01-01

    Low-level, hazardous, and mixed waste disposal sites normally require some form of plant material to prevent erosion of the final closure cap. Waste disposal sites are closed and capped in a complex scientific manner to minimize water infiltration and percolation into and through the waste material. Turf type grasses are currently being used as a vegetative cover for most sites. Consequently, the sites require periodic mowing and other expensive annual maintenance practices. The purpose of this five year study was to evaluate alternative plant material for use on wastes sites that is quickly and easily established and economically maintained, retards water infiltration, provides maximum year-round evapotranspiration, is ecologically acceptable and does not harm the closure cap. The results of the study are described in this report and suggest that two species of bamboo (Phyllostachys bissetii and P. rubromarainata) can be utilized to provide long lived, low maintenance, climax vegetation for the waste sites. These large species of bamboo will also reduce the probability of intrusion by humans, animals and deeply rooted plant species.

  1. Catawba Science Center solar activities. Final report

    SciTech Connect

    1983-01-01

    Two demonstration solar water heaters were built. One was to be used at the Science Center and the other with traveling programs. This was completed and both units are being used for these programs which continue. We were able to build a library of 99 solar energy books and booklets that are available to the public for reference. We also conducted programs for 683 students of all ages. The culminating activity was the planned Energy Awareness Festival. This was held on September 26, 1981 and attracted 450 area citizens. We offered free exhibit space and hosted 17 exhibitors.

  2. Ground-water protection standards for inactive uranium tailings sites (40 CFR 192): Background information for final rule. Final report

    SciTech Connect

    Not Available

    1989-03-01

    The Final Background Information Document summarizes the information and data considered by the Agency in developing the ground-water protection standards. The report presents a brief description of the Title II ground water standard and how it can be used to develop the Title I rulemaking. A description of the 24 designated uranium-tailings sites and their current status in the DOE remedial-action program is included as well as a detailed analysis of the available data on the ground water in the vicinity of 14 of the 24 sites. It also describes different methods that can be used for the restoration of ground water and the costs of using these restoration methods.

  3. [Structural regularities in activated cleavage sites of thrombin receptors].

    PubMed

    Mikhaĭlik, I V; Verevka, S V

    1999-01-01

    Comparison of thrombin receptors activation splitting sites sequences testifies to their similarity both in activation splitting sites of protein precursors and protein proteinase inhibitors reactive sites. In all these sites corresponded to effectory sites P2'-positions are placed by hydrophobic amino-acids only. The regularity defined conforms with previous thesis about the role of effectory S2'-site in regulation of the processes mediated by serine proteinases.

  4. Final Hanford Comprehensive Land-Use Plan Environmental Impact Statement, Hanford Site, Richland, Washington

    SciTech Connect

    N /A

    1999-10-01

    This Final ''Hanford Comprehensive Land-Use Plan Environmental Impact Statement'' (HCP EIS) is being used by the Department of Energy (DOE) and its nine cooperating and consulting agencies to develop a comprehensive land-use plan (CLUP) for the Hanford Site. The DOE will use the Final HCP EIS as a basis for a Record of Decision (ROD) on a CLUP for the Hanford Site. While development of the CLUP will be complete with release of the HCP EIS ROD, full implementation of the CLUP is expected to take at least 50 years. Implementation of the CLUP would begin a more detailed planning process for land-use and facility-use decisions at the Hanford Site. The DOE would use the CLUP to screen proposals. Eventually, management of Hanford Site areas would move toward the CLUP land-use goals. This CLUP process could take more than 50 years to fully achieve the land-use goals.

  5. Characterize and explore potential sites and prepare research and development plan (site investigation study). Final draft. Task 2. Milestone report

    SciTech Connect

    1980-12-01

    Phase II of a 5-phase overall compressed air energy storage (CAES) development program was performed to characterize and explore potential CAES sites and to prepare a research and development plan. This volume for Phase II activities contains an evaluation of the suitability of seven selected sites to undergo field drilling and air injection testing; a bibliography; results of a literature search on the effects of air injection of aquifer-caprock well systems; reservoir data for the sites; cost estimates; and predicted potential risks from a CAES plant. (LCL)

  6. Final Record of Decision/Remedial Action Plan, Nine Sites, Sierra Army Depot, Lassen County, California.

    DTIC Science & Technology

    1996-10-01

    section provides the declaration portion of the ROD /RAP for the Construction Debris Landfill. 5.1.1 Location The Construction Debris Landfill is...and Role of Response Action This ROD /RAP presents the final response action for the Construction Debris Landfill. This site poses no potential threat...AMMUNITION DEMILITARIZATION AND RENOVATION AREA BUILDING 1003 AREA CHEMICAL BURIAL SITE CONSTRUCTION DEBRIS LANDFILL EXISTING LANDFILL EXISTING

  7. Brownian aggregation rate of colloid particles with several active sites

    SciTech Connect

    Nekrasov, Vyacheslav M.; Yurkin, Maxim A.; Chernyshev, Andrei V.; Polshchitsin, Alexey A.; Yakovleva, Galina E.; Maltsev, Valeri P.

    2014-08-14

    We theoretically analyze the aggregation kinetics of colloid particles with several active sites. Such particles (so-called “patchy particles”) are well known as chemically anisotropic reactants, but the corresponding rate constant of their aggregation has not yet been established in a convenient analytical form. Using kinematic approximation for the diffusion problem, we derived an analytical formula for the diffusion-controlled reaction rate constant between two colloid particles (or clusters) with several small active sites under the following assumptions: the relative translational motion is Brownian diffusion, and the isotropic stochastic reorientation of each particle is Markovian and arbitrarily correlated. This formula was shown to produce accurate results in comparison with more sophisticated approaches. Also, to account for the case of a low number of active sites per particle we used Monte Carlo stochastic algorithm based on Gillespie method. Simulations showed that such discrete model is required when this number is less than 10. Finally, we applied the developed approach to the simulation of immunoagglutination, assuming that the formed clusters have fractal structure.

  8. Small Sites in the Central Hueco Bolson: A Final Report on Project 90-11

    DTIC Science & Technology

    1998-01-01

    8217 if i| a.an a»»»,»» »| l ’ |rt Jpfcrta.» Watt™ a»»«» l » i WmaWnarahr ozRfsirsiLT^miS^r LttrOlTMTE 4. inuuDSMinu Srrall Sites in the Central...Analysis of Flotation Samples from 16 Archeological Sites, by Glenna Dean, Ph.D 440 Appendix L - Pollen and Flotation Analyses of Samples from 16...in excavation. The final phase of the project, Phase 4, involved syntheses of data and production of this report. The project recorded 176 sites and

  9. Stressor Identification (Si) at Contaminated Sites: Upper Arkansas River, Colorado (Final)

    EPA Science Inventory

    sites/production/files/2015-07/ca_gulch_cover.jpg" vspace = "5" hspace="5" width = "218" height = "286" align="right" border="1" alt="Cover of the CADDIS Arkansas River, CO Case Study Final Report "> This report describes a causal assessment for...

  10. Evaluating Ecological Risk to Invertebrate Receptors from PAHs in Sediments at Hazardous Waste Sites (Final Report)

    EPA Science Inventory

    EPA's Ecological Risk Assessment Support Center (ERASC) announced the release of the final report, Evaluating Ecological Risk to Invertebrate Receptors from PAHs in Sediments at Hazardous Waste Sites. The report provides an overview of an approach for assessing risk to ...

  11. EPA Revises Final Cleanup Plan for Ringwood Mines Superfund Site in Ringwood, New Jersey

    EPA Pesticide Factsheets

    (New York, N.Y.) The U.S. Environmental Protection Agency has determined that the Borough of Ringwood has satisfied the criteria specified in EPA's June 30, 2014 final cleanup plan for the Ringwood Mines Superfund site that allows for a recycling center to

  12. Nesting habitat and nest site selection by the bald eagle in Maryland. Final report

    SciTech Connect

    Mosher, J.A.; Andrew, J.M.

    1981-07-01

    Habitat at 70 bald eagle (Haliaeetus leucocephalus) nest sites was quantified and compared with evaluations at 139 random habitat plots located in the Chesapeake Bay region of Maryland. Bald eagles selected vegetationally open habitats near water and away from selected human activities relative to random habitat plots. Successful nest sites were located in denser forest stands farther from water and unoccupied structures than unsuccessful nest sites.

  13. Preliminary siting activities for new waste handling facilities at the Idaho National Engineering Laboratory

    SciTech Connect

    Taylor, D.D.; Hoskinson, R.L.; Kingsford, C.O.; Ball, L.W.

    1994-09-01

    The Idaho Waste Processing Facility, the Mixed and Low-Level Waste Treatment Facility, and the Mixed and Low-Level Waste Disposal Facility are new waste treatment, storage, and disposal facilities that have been proposed at the Idaho National Engineering Laboratory (INEL). A prime consideration in planning for such facilities is the selection of a site. Since spring of 1992, waste management personnel at the INEL have been involved in activities directed to this end. These activities have resulted in the (a) identification of generic siting criteria, considered applicable to either treatment or disposal facilities for the purpose of preliminary site evaluations and comparisons, (b) selection of six candidate locations for siting,and (c) site-specific characterization of candidate sites relative to selected siting criteria. This report describes the information gathered in the above three categories for the six candidate sites. However, a single, preferred site has not yet been identified. Such a determination requires an overall, composite ranking of the candidate sites, which accounts for the fact that the sites under consideration have different advantages and disadvantages, that no single site is superior to all the others in all the siting criteria, and that the criteria should be assigned different weighing factors depending on whether a site is to host a treatment or a disposal facility. Stakeholder input should now be solicited to help guide the final selection. This input will include (a) siting issues not already identified in the siting, work to date, and (b) relative importances of the individual siting criteria. Final site selection will not be completed until stakeholder input (from the State of Idaho, regulatory agencies, the public, etc.) in the above areas has been obtained and a strategy has been developed to make a composite ranking of all candidate sites that accounts for all the siting criteria.

  14. MYST protein acetyltransferase activity requires active site lysine autoacetylation.

    PubMed

    Yuan, Hua; Rossetto, Dorine; Mellert, Hestia; Dang, Weiwei; Srinivasan, Madhusudan; Johnson, Jamel; Hodawadekar, Santosh; Ding, Emily C; Speicher, Kaye; Abshiru, Nebiyu; Perry, Rocco; Wu, Jiang; Yang, Chao; Zheng, Y George; Speicher, David W; Thibault, Pierre; Verreault, Alain; Johnson, F Bradley; Berger, Shelley L; Sternglanz, Rolf; McMahon, Steven B; Côté, Jacques; Marmorstein, Ronen

    2012-01-04

    The MYST protein lysine acetyltransferases are evolutionarily conserved throughout eukaryotes and acetylate proteins to regulate diverse biological processes including gene regulation, DNA repair, cell-cycle regulation, stem cell homeostasis and development. Here, we demonstrate that MYST protein acetyltransferase activity requires active site lysine autoacetylation. The X-ray crystal structures of yeast Esa1 (yEsa1/KAT5) bound to a bisubstrate H4K16CoA inhibitor and human MOF (hMOF/KAT8/MYST1) reveal that they are autoacetylated at a strictly conserved lysine residue in MYST proteins (yEsa1-K262 and hMOF-K274) in the enzyme active site. The structure of hMOF also shows partial occupancy of K274 in the unacetylated form, revealing that the side chain reorients to a position that engages the catalytic glutamate residue and would block cognate protein substrate binding. Consistent with the structural findings, we present mass spectrometry data and biochemical experiments to demonstrate that this lysine autoacetylation on yEsa1, hMOF and its yeast orthologue, ySas2 (KAT8) occurs in solution and is required for acetylation and protein substrate binding in vitro. We also show that this autoacetylation occurs in vivo and is required for the cellular functions of these MYST proteins. These findings provide an avenue for the autoposttranslational regulation of MYST proteins that is distinct from other acetyltransferases but draws similarities to the phosphoregulation of protein kinases.

  15. MYST protein acetyltransferase activity requires active site lysine autoacetylation

    PubMed Central

    Yuan, Hua; Rossetto, Dorine; Mellert, Hestia; Dang, Weiwei; Srinivasan, Madhusudan; Johnson, Jamel; Hodawadekar, Santosh; Ding, Emily C; Speicher, Kaye; Abshiru, Nebiyu; Perry, Rocco; Wu, Jiang; Yang, Chao; Zheng, Y George; Speicher, David W; Thibault, Pierre; Verreault, Alain; Johnson, F Bradley; Berger, Shelley L; Sternglanz, Rolf; McMahon, Steven B; Côté, Jacques; Marmorstein, Ronen

    2012-01-01

    The MYST protein lysine acetyltransferases are evolutionarily conserved throughout eukaryotes and acetylate proteins to regulate diverse biological processes including gene regulation, DNA repair, cell-cycle regulation, stem cell homeostasis and development. Here, we demonstrate that MYST protein acetyltransferase activity requires active site lysine autoacetylation. The X-ray crystal structures of yeast Esa1 (yEsa1/KAT5) bound to a bisubstrate H4K16CoA inhibitor and human MOF (hMOF/KAT8/MYST1) reveal that they are autoacetylated at a strictly conserved lysine residue in MYST proteins (yEsa1-K262 and hMOF-K274) in the enzyme active site. The structure of hMOF also shows partial occupancy of K274 in the unacetylated form, revealing that the side chain reorients to a position that engages the catalytic glutamate residue and would block cognate protein substrate binding. Consistent with the structural findings, we present mass spectrometry data and biochemical experiments to demonstrate that this lysine autoacetylation on yEsa1, hMOF and its yeast orthologue, ySas2 (KAT8) occurs in solution and is required for acetylation and protein substrate binding in vitro. We also show that this autoacetylation occurs in vivo and is required for the cellular functions of these MYST proteins. These findings provide an avenue for the autoposttranslational regulation of MYST proteins that is distinct from other acetyltransferases but draws similarities to the phosphoregulation of protein kinases. PMID:22020126

  16. Final long-term surveillance plan for the Spook, Wyoming, disposal site

    SciTech Connect

    1993-01-01

    A general license for the custody and long-term care of DOE Uranium Mill Tailings Remedial Action (UMTRA) Project permanent disposal sites was issued by the US Nuclear Regulatory Commission (NRC), and became effective on November 29, 1990. The general license will be in effect for a specific disposal site when the NRC accepts the disposal site`s long-term surveillance plan (LTSP) and concurs that remedial action is complete at that site. This document describes in detail the long-term surveillance activities for the Spook, Wyoming, disposal site, including monitoring, maintenance, and emergency measures necessary to fulfill the conditions of the general license, and to ensure that the disposal cell continues to comply with the UMTRA design standards.

  17. Challenges with Final Status Surveys at a Large Decommissioning Site - 13417

    SciTech Connect

    Downey, Heath; Collopy, Peter; Shephard, Eugene; Walter, Nelson; Conant, John

    2013-07-01

    As part of decommissioning a former nuclear fuel manufacturing site, one of the crucial final steps is to conduct Final Status Surveys (FSS) in order to demonstrate compliance with the release criteria. At this decommissioning site, the area for FSS was about 100 hectares (248 acres) and included varying terrain, wooded areas, ponds, excavations, buildings and a brook. The challenges in performing the FSS included determining location, identifying FSS units, logging gamma walkover survey data, determining sample locations, managing water in excavations, and diverting water in the brook. The approaches taken to overcome these challenges will be presented in the paper. The paper will present and discuss lessons learned that will aid others in the FSS process. (authors)

  18. First Principles Computational Study of the Active Site of Arginase

    SciTech Connect

    Ivanov, Ivaylo; Klien, Micheal

    2004-01-14

    Ab initio density functional theory (DFT) methods were used to investigate the structural features of the active site of the binuclear enzyme rat liver arginase. Special emphasis was placed on the crucial role of the second shell ligand interactions. These interactions were systematically studied by performing calculations on models of varying size. It was determined that a water molecule, and not hydroxide, is the bridging exogenous ligand. The carboxylate ligands facilitate the close approach of the Mn (II) ions by attenuating the metal-metal electrostatic repulsion. Of the two metals, MnA was shown to carry a larger positive charge. Analysis of the electronic properties of the active site revealed that orbitals involving the terminal Asp234 residue, as well as the flexible -1,1 bridging Asp232, lie at high energies, suggesting weaker coordination. This is reflected in certain structural variability present in our models and is also consistent with recent experimental findings. Finally, implications of our findings for the biological function of the enzyme are delineated.

  19. Development and final design of FAME active array

    NASA Astrophysics Data System (ADS)

    Farkas, Szigfrid; Agócs, Tibor; Aitink-Kroes, Gabby; Bettonvil, Felix; Black, Martin; Hugot, Emmanuel; Jaskó, Attila; Miller, Chris; Schnetler, Hermine; van Duffelen, Farian; Venema, Lars

    2016-07-01

    FAME (Freeform Active Mirror Experiment - part of the FP7 OPTICON/FP7 development programme) intends to demonstrate the huge potential of active mirrors and freeform optical surfaces. Freeform active surfaces can help to address the new challenges of next generation astronomical instruments, which are bigger, more complex and have tighter specifications than their predecessors. The FAME design consists of a pre-formed, deformable thin mirror sheet with an active support system. The thin face sheet provides a close to final surface shape with very high surface quality. The active array provides the support, and through actuation, the control to achieve final surface shape accuracy. In this paper the development path, trade-offs and demonstrator design of the FAME active array is presented. The key step in the development process of the active array is the design of the mechanical structure and especially the optimization of the actuation node positions, where the actuator force is transmitted to the thin mirror sheet. This is crucial for the final performance of the mirror where the aim is to achieve an accurate surface shape, with low residual (high order) errors using the minimum number of actuators. These activities are based on the coupling of optical and mechanical engineering, using analytical and numerical methods, which results in an active array with optimized node positions and surface shape.

  20. Comment and response document for the final remedial action plan and site design for stabilization of the inactive uranium mill tailings sites at Slick Rock, Colorado. Revision 2

    SciTech Connect

    1996-05-01

    This document for the final remedial action plan and site design has been prepared for US Department of Energy Environmental Restoration Division as part of the Uranium Mill Tailings Remedial Action plan. Comments and responses are included for the site design for stabilization of the inactive uranium mill tailings sites at Slick Rock, Colorado.

  1. Characterize and explore potential sites and prepare research and development plan (site investigation study). Final draft. Task 2. Milestone report

    SciTech Connect

    1980-12-01

    A specific research and development plan to investigate the behavior and suitability of aquifers as compressed air energy storage (CAES) sites is presented. The proposed effort will evaluate present uncertainties in the performance of the underground energy storage subsystem and its impact on above ground plant design and cost. The project is planned to provide the utility industry with a quantitative basis for confidence that financial commitment to a demonstration plant and subsequent expansion is justified and poses acceptable risks. Activities in Phase II of a 5-phase overall CAES development program are reported. Information is included on the development of field testing specifications and schedules; selection of specific site for the conceptual design; development plan and schedule for the media site; development of analytical models of aquifer airflow; and well drilling requirements. As a result of these studies 14 sites in Illinois and Indiana were evaluated, 7 were ranked for suitability for CAES, and 4 were selected for possible use in the field testing program. Test procedures, the mathematical models and drilling requirments were developed. (LCL)

  2. Final work plan: Expedited Site Characterization of the IES Industries, Inc., Site at Marshalltown, Iowa. Ames Expedited Site Characterization Project, Version 1.0

    SciTech Connect

    Not Available

    1994-04-04

    The overall goal of the Ames Laboratory Expedited Site Characterization (ESC) project is to evaluate and promote both innovative and state-of-the-practice site characterization and/or monitoring technologies. This will be accomplished by fielding both types of technologies together in the context of an expedited site characterization. The first site will be at a former manufactured gas plant (FMGP) in Marshalltown, Iowa. The project will field three areas of technology: geophysical, analytical, and data fusion. Geophysical technologies are designed to understand the subsurface geology to help predict fate and transport of the target contaminants. Analytical technologies/methods are designed to detect and quantify the target contaminants. Data fusion technology consists of software systems designed to rapidly integrate or fuse all site information into a conceptual site model that then becomes the decision making tool for the site team to plan subsequent sampling activity. Not all of the contaminants present can be located at the action level. Polynuclear aromatic hydrocarbons (PAHs) are the signature organics associated with the coal tar activities that took place at the site. As a result, PAHs were selected as the target compounds. Screening analytical instruments and nonintrusive geophysical techniques will be fielded to qualitatively map the spatial contaminant distribution. Soil gas surveys, immunoassay testing (IMA), innovative optical techniques, and passive organic sorbent sensors will be deployed along with the geophysical methods. Gas chromatography/mass spectrometry (GC/MS) instruments and a cone penetrometer system equipped with a laser-induced fluorescence (LIF) probe will quantitatively map the action level edges of the PAH plume(s). Samples will be taken both by the cone penetrometer test system (CPT) and the Geoprobe {reg_sign} sampler system.

  3. The active site of ribulose-bisphosphate carboxylase/oxygenase

    SciTech Connect

    Hartman, F.C.

    1991-01-01

    The active site of ribulose-bisphosphate carboxylase/oxygenase requires interacting domains of adjacent, identical subunits. Most active-site residues are located within the loop regions of an eight-stranded {beta}/{alpha}-barrel which constitutes the larger C-terminal domain; additional key residues are located within a segment of the smaller N-terminal domain which partially covers the mouth of the barrel. Site-directed mutagenesis of the gene encoding the enzyme from Rhodospirillum rubrum has been used to delineate functions of active-site residues. 6 refs., 2 figs.

  4. DOE site performance assessment activities. Radioactive Waste Technical Support Program

    SciTech Connect

    Not Available

    1990-07-01

    Information on performance assessment capabilities and activities was collected from eight DOE sites. All eight sites either currently dispose of low-level radioactive waste (LLW) or plan to dispose of LLW in the near future. A survey questionnaire was developed and sent to key individuals involved in DOE Order 5820.2A performance assessment activities at each site. The sites surveyed included: Hanford Site (Hanford), Idaho National Engineering Laboratory (INEL), Los Alamos National Laboratory (LANL), Nevada Test Site (NTS), Oak Ridge National Laboratory (ORNL), Paducah Gaseous Diffusion Plant (Paducah), Portsmouth Gaseous Diffusion Plant (Portsmouth), and Savannah River Site (SRS). The questionnaire addressed all aspects of the performance assessment process; from waste source term to dose conversion factors. This report presents the information developed from the site questionnaire and provides a comparison of site-specific performance assessment approaches, data needs, and ongoing and planned activities. All sites are engaged in completing the radioactive waste disposal facility performance assessment required by DOE Order 5820.2A. Each site has achieved various degrees of progress and have identified a set of critical needs. Within several areas, however, the sites identified common needs and questions.

  5. Savannah River Site prioritization of transition activities

    SciTech Connect

    Finley, R.H.

    1993-11-01

    Effective management of SRS conversion from primarily a production facility to other missions (or Decontamination and Decommissioning (D&D)) requires a systematic and consistent method of prioritizing the transition activities. This report discusses the design of a prioritizing method developed to achieve systematic and consistent methods of prioritizing these activities.

  6. Comment and response document on the final remedial action plan and site design for stabilization of the inactive Uranium Mill Tailings Site at Lakeview, Oregon

    SciTech Connect

    Not Available

    1991-10-01

    This report contains comments provided by the Oregon Department of Energy and responses to these comments on the final remedial action plan for the inactive uranium mill tailings site at Lakeview, Oregon.

  7. Safety Oversight of Decommissioning Activities at DOE Nuclear Sites

    SciTech Connect

    Zull, Lawrence M.; Yeniscavich, William

    2008-01-15

    The Defense Nuclear Facilities Safety Board (Board) is an independent federal agency established by Congress in 1988 to provide nuclear safety oversight of activities at U.S. Department of Energy (DOE) defense nuclear facilities. The activities under the Board's jurisdiction include the design, construction, startup, operation, and decommissioning of defense nuclear facilities at DOE sites. This paper reviews the Board's safety oversight of decommissioning activities at DOE sites, identifies the safety problems observed, and discusses Board initiatives to improve the safety of decommissioning activities at DOE sites. The decommissioning of former defense nuclear facilities has reduced the risk of radioactive material contamination and exposure to the public and site workers. In general, efforts to perform decommissioning work at DOE defense nuclear sites have been successful, and contractors performing decommissioning work have a good safety record. Decommissioning activities have recently been completed at sites identified for closure, including the Rocky Flats Environmental Technology Site, the Fernald Closure Project, and the Miamisburg Closure Project (the Mound site). The Rocky Flats and Fernald sites, which produced plutonium parts and uranium materials for defense needs (respectively), have been turned into wildlife refuges. The Mound site, which performed R and D activities on nuclear materials, has been converted into an industrial and technology park called the Mound Advanced Technology Center. The DOE Office of Legacy Management is responsible for the long term stewardship of these former EM sites. The Board has reviewed many decommissioning activities, and noted that there are valuable lessons learned that can benefit both DOE and the contractor. As part of its ongoing safety oversight responsibilities, the Board and its staff will continue to review the safety of DOE and contractor decommissioning activities at DOE defense nuclear sites.

  8. Final Review of Safety Assessment Issues at Savannah River Site, August 2011

    SciTech Connect

    Napier, Bruce A.; Rishel, Jeremy P.; Bixler, Nathan E.

    2011-12-15

    At the request of Savannah River Nuclear Solutions (SRNS) management, a review team composed of experts in atmospheric transport modeling for environmental radiation dose assessment convened at the Savannah River Site (SRS) on August 29-30, 2011. Though the meeting was prompted initially by suspected issues related to the treatment of surface roughness inherent in the SRS meteorological dataset and its treatment in the MELCOR Accident Consequence Code System Version 2 (MACCS2), various topical areas were discussed that are relevant to performing safety assessments at SRS; this final report addresses these topical areas.

  9. Controlled Orientation of Active Sites in a Nanostructured Multienzyme Complex

    PubMed Central

    Lim, Sung In; Yang, Byungseop; Jung, Younghan; Cha, Jaehyun; Cho, Jinhwan; Choi, Eun-Sil; Kim, Yong Hwan; Kwon, Inchan

    2016-01-01

    Multistep cascade reactions in nature maximize reaction efficiency by co-assembling related enzymes. Such organization facilitates the processing of intermediates by downstream enzymes. Previously, the studies on multienzyme nanocomplexes assembled on DNA scaffolds demonstrated that closer interenzyme distance enhances the overall reaction efficiency. However, it remains unknown how the active site orientation controlled at nanoscale can have an effect on multienzyme reaction. Here, we show that controlled alignment of active sites promotes the multienzyme reaction efficiency. By genetic incorporation of a non-natural amino acid and two compatible bioorthogonal chemistries, we conjugated mannitol dehydrogenase to formate dehydrogenase with the defined active site arrangement with the residue-level accuracy. The study revealed that the multienzyme complex with the active sites directed towards each other exhibits four-fold higher relative efficiency enhancement in the cascade reaction and produces 60% more D-mannitol than the other complex with active sites directed away from each other. PMID:28004799

  10. Interim final guidance package on funding CERCLA State-enforcement actions at NPL sites

    SciTech Connect

    Not Available

    1988-04-07

    The directive outlines requirements, conditions, and limitations for State funding under a CERCLA cooperative agreement of CERCLA enforcement actions at National Priorities List sites. The guidance is divided into four subcomponents: 9831.6 a, b, c, and d. The directive supersedes directive no. 9831.1-1a CERCLA Funding of State Oversight of Potentially Responsible Parties (PRPs), dated October 1, 1986, and directive no. 9831.3 dated October 1, 1986 CERCLA Funding of State Enforcement Activities at NPL Sites, - Interim Draft Guidance.

  11. Nondiscrimination in Health Programs and Activities. Final rule.

    PubMed

    2016-05-18

    This final rule implements Section 1557 of the Affordable Care Act (ACA) (Section 1557). Section 1557 prohibits discrimination on the basis of race, color, national origin, sex, age, or disability in certain health programs and activities. The final rule clarifies and codifies existing nondiscrimination requirements and sets forth new standards to implement Section 1557, particularly with respect to the prohibition of discrimination on the basis of sex in health programs other than those provided by educational institutions and the prohibition of various forms of discrimination in health programs administered by the Department of Health and Human Services (HHS or the Department) and entities established under Title I of the ACA. In addition, the Secretary is authorized to prescribe the Department's governance, conduct, and performance of its business, including, here, how HHS will apply the standards of Section 1557 to HHS-administered health programs and activities.

  12. Perspective: On the active site model in computational catalyst screening

    NASA Astrophysics Data System (ADS)

    Reuter, Karsten; Plaisance, Craig P.; Oberhofer, Harald; Andersen, Mie

    2017-01-01

    First-principles screening approaches exploiting energy trends in surface adsorption represent an unparalleled success story in recent computational catalysis research. Here we argue that our still limited understanding of the structure of active sites is one of the major bottlenecks towards an ever extended and reliable use of such computational screening for catalyst discovery. For low-index transition metal surfaces, the prevalently chosen high-symmetry (terrace and step) sites offered by the nominal bulk-truncated crystal lattice might be justified. For more complex surfaces and composite catalyst materials, computational screening studies will need to actively embrace a considerable uncertainty with respect to what truly are the active sites. By systematically exploring the space of possible active site motifs, such studies might eventually contribute towards a targeted design of optimized sites in future catalysts.

  13. Diffusional correlations among multiple active sites in a single enzyme.

    PubMed

    Echeverria, Carlos; Kapral, Raymond

    2014-04-07

    Simulations of the enzymatic dynamics of a model enzyme containing multiple substrate binding sites indicate the existence of diffusional correlations in the chemical reactivity of the active sites. A coarse-grain, particle-based, mesoscopic description of the system, comprising the enzyme, the substrate, the product and solvent, is constructed to study these effects. The reactive and non-reactive dynamics is followed using a hybrid scheme that combines molecular dynamics for the enzyme, substrate and product molecules with multiparticle collision dynamics for the solvent. It is found that the reactivity of an individual active site in the multiple-active-site enzyme is reduced substantially, and this effect is analyzed and attributed to diffusive competition for the substrate among the different active sites in the enzyme.

  14. Remedial action at the Acid/Pueblo Canyon site, Los Alamos, New Mexico. Final report

    SciTech Connect

    1984-10-01

    The Acid/Pueblo Canyon site (TA-45) was designated in 1976 for remedial action under the Formerly Utilized Sites Remedial Action Program (FUSRAP). During the period 1943 to 1964 untreated and treated liquid wastes generated by nuclear weapons research activities at the Los Alamos Scientific Laboratory (LASL) were discharged into the two canyons. A survey of the site conducted by LASL in 1976 to 1977 identified two areas where radiological contamination exceeded criteria levels. The selected remedial action was based on extensive radiological characterization and comprehensive engineering assessments and comprised the excavation and disposal of 390 yd/sup 3/ of contaminated soil and rock. This document describes the background to the remedial action, the parties involved in administering and executing it, the chronology of the work, verification of the adequacy of the remedial action, and the cost incurred. 14 references, 5 figures, 5 tables.

  15. Final Report: Imaging of Buried Nanoscale Optically Active Materials

    SciTech Connect

    Appelbaum, Ian

    2011-07-05

    This is a final report covering work done at University of Maryland to develop a Ballistic Electron Emission Luminescence (BEEL) microscope. This technique was intended to examine the carrier transport and photon emission in deeply buried optically-active layers and thereby provide a means for materials science to unmask the detailed consequences of experimentally controllable growth parameters, such as quantum dot size, statistics and orientation, and defect density and charge recombination pathways.

  16. Active Site Hydrophobicity and the Convergent Evolution of Paraoxonase Activity in Structurally Divergent Enzymes: The Case of Serum Paraoxonase 1

    PubMed Central

    2016-01-01

    Serum paraoxonase 1 (PON1) is a native lactonase capable of promiscuously hydrolyzing a broad range of substrates, including organophosphates, esters, and carbonates. Structurally, PON1 is a six-bladed β-propeller with a flexible loop (residues 70–81) covering the active site. This loop contains a functionally critical Tyr at position 71. We have performed detailed experimental and computational analyses of the role of selected Y71 variants in the active site stability and catalytic activity in order to probe the role of Y71 in PON1’s lactonase and organophosphatase activities. We demonstrate that the impact of Y71 substitutions on PON1’s lactonase activity is minimal, whereas the kcat for the paraoxonase activity is negatively perturbed by up to 100-fold, suggesting greater mutational robustness of the native activity. Additionally, while these substitutions modulate PON1’s active site shape, volume, and loop flexibility, their largest effect is in altering the solvent accessibility of the active site by expanding the active site volume, allowing additional water molecules to enter. This effect is markedly more pronounced in the organophosphatase activity than the lactonase activity. Finally, a detailed comparison of PON1 to other organophosphatases demonstrates that either a similar “gating loop” or a highly buried solvent-excluding active site is a common feature of these enzymes. We therefore posit that modulating the active site hydrophobicity is a key element in facilitating the evolution of organophosphatase activity. This provides a concrete feature that can be utilized in the rational design of next-generation organophosphate hydrolases that are capable of selecting a specific reaction from a pool of viable substrates. PMID:28026940

  17. Remedial action plan and site design for stabilization of the inactive uranium mill tailings sites at Rifle, Colorado. Volume 2, Appendices D and E: Final report

    SciTech Connect

    Not Available

    1992-02-01

    This appendix assesses the present conditions and data gathered about the two inactive uranium mill tailings sites near Rifle, Colorado, and the designated disposal site six miles north of Rifle in the area of Estes Gulch. It consolidates available engineering, radiological, geotechnical, hydrological, meteorological, and other information pertinent to the design of the Remedial Action Plan (RAP). The data characterize conditions at the mill, tailings, and disposal site so that the Remedial Action Contractor (RAC) may complete final designs for the remedial actions.

  18. Robotics at Savannah River site: activity report

    SciTech Connect

    Byrd, J.S.

    1984-09-01

    The objectives of the Robotics Technology Group at the Savannah River Laboratory are to employ modern industrial robots and to develop unique automation and robotic systems to enhance process operations at the Savannah River site (SRP and SRL). The incentives are to improve safety, reduce personnel radiation exposure, improve product quality and productivity, and to reduce operating costs. During the past year robotic systems have been installed to fill chemical dilution vials in a SRP laboratory at 772-F and remove radioactive waste materials in the SRL Californium Production Facility at 773-A. A robotic system to lubricate an extrusion press has been developed and demonstrated in the SRL robotics laboratory and is scheduled for installation at the 321-M fuel fabrication area. A mobile robot was employed by SRP for a radiation monitoring task at a waste tank top in H-Area. Several other robots are installed in the SRL robotics laboratories and application development programs are underway. The status of these applications is presented in this report.

  19. Active sites of thioredoxin reductases: why selenoproteins?

    PubMed

    Gromer, Stephan; Johansson, Linda; Bauer, Holger; Arscott, L David; Rauch, Susanne; Ballou, David P; Williams, Charles H; Schirmer, R Heiner; Arnér, Elias S J

    2003-10-28

    Selenium, an essential trace element for mammals, is incorporated into a selected class of selenoproteins as selenocysteine. All known isoenzymes of mammalian thioredoxin (Trx) reductases (TrxRs) employ selenium in the C-terminal redox center -Gly-Cys-Sec-Gly-COOH for reduction of Trx and other substrates, whereas the corresponding sequence in Drosophila melanogaster TrxR is -Ser-Cys-Cys-Ser-COOH. Surprisingly, the catalytic competence of these orthologous enzymes is similar, whereas direct Sec-to-Cys substitution of mammalian TrxR, or other selenoenzymes, yields almost inactive enzyme. TrxRs are therefore ideal for studying the biology of selenocysteine by comparative enzymology. Here we show that the serine residues flanking the C-terminal Cys residues of Drosophila TrxRs are responsible for activating the cysteines to match the catalytic efficiency of a selenocysteine-cysteine pair as in mammalian TrxR, obviating the need for selenium. This finding suggests that the occurrence of selenoenzymes, which implies that the organism is selenium-dependent, is not necessarily associated with improved enzyme efficiency. Our data suggest that the selective advantage of selenoenzymes is a broader range of substrates and a broader range of microenvironmental conditions in which enzyme activity is possible.

  20. Report on Lessons Learned from the NP 2010 Early Site Permit Program FINAL REPORT

    SciTech Connect

    2008-03-26

    guidance for developing and reviewing ESP applications, issues involving ESP plant parameters, and suggestions for future ESP applicants. The development, submittal, and issuance of these first ESPs under DOE’s NP 2010 program started the momentum to exercise NRC’s new 10 CFR Part 52 licensing process. Several key questions that define critical issues regarding the effectiveness of regulations pertaining to ESPs have been identified and summarized in this report. However, the final resolution of whether the ESP component of the Part 52 process significantly contributes to the predictability in nuclear power plant licensing requires more experience and time, such as the completion of the ongoing combined Construction and Operating License (COL) process for the North Anna and Grand Gulf sites. The three ESP project participants prepared and submitted to DOE lessons learned reports from their experience in developing, submitting, and receiving an ESP. This document summarizes these reports, which are appended hereto. The Nuclear Energy Institute (http://www.nei.org/) and NRC (http://www.nrc.gov/) have also prepared reports regarding their perspectives on lessons learned during the ESP process. Their documents can be accessed on their respective web sites. Following is a summary of the lessons learned from the NP 2010 ESP projects. Effectiveness of the ESP Process: In general, the ESP process is expected (subject to demonstration of the ESP finality provisions in the North Anna and Grand Gulf ESPs) to provide high value for applicants as a site banking and risk mitigation strategy. However, several aspects of the initial process, such as NRC hearings and determining an acceptable approach to the NRC’s Emergency Planning requirements, proved challenging for the applicants. Project Execution: Initial regulatory and industry guidance for planning and executing an ESP application program proved to be insufficient to address NRC’s document review expectations. However

  1. Community Update on Site Activities, July 19, 2013

    EPA Pesticide Factsheets

    In an effort to engage and inform community members interested in the New Bedford Harbor Superfund Site cleanup, EPA will be issuing periodic topic-based fact sheets that will provide background information and updates about ongoing activities.

  2. Final report on the radiological surveys of designated DX firing sites at Los Alamos National Laboratory

    SciTech Connect

    1996-09-09

    CHEMRAD was contracted by Los Alamos National Laboratory to perform USRADS{reg_sign} (UltraSonic Ranging And Data System) radiation scanning surveys at designated DX Sites at the Los Alamos National Laboratory. The primary purpose of these scanning surveys was to identify the presence of Depleted Uranium (D-38) resulting from activities at the DX Firing Sites. This effort was conducted to update the most recent surveys of these areas. This current effort was initiated with site orientation on August 12, 1996. Surveys were completed in the field on September 4, 1996. This Executive Summary briefly presents the major findings of this work. The detail survey results are presented in the balance of this report and are organized by Technical Area and Site number in section 2. This organization is not in chronological order. USRADS and the related survey methods are described in section 3. Quality Control issues are addressed in section 4. Surveys were conducted with an array of radiation detectors either mounted on a backpack frame for man-carried use (Manual mode) or on a tricycle cart (RadCart mode). The array included radiation detectors for gamma and beta surface near surface contamination as well as dose rate at 1 meter above grade. The radiation detectors were interfaced directly to an USRADS 2100 Data Pack.

  3. Site operator program final report for fiscal years 1992 through 1996

    SciTech Connect

    Francfort, J.E.; Bassett, R.R.; Birasco, S.

    1998-01-01

    The Site Operator Program was an electric vehicle testing and evaluation program sponsored by US Department of Energy and managed at the Idaho National Engineering and Environmental Laboratory. The Program`s goals included the field evaluation of electric vehicles in real-world applications and environments; the support of electric vehicle technology advancement; the development of infrastructure elements necessary to support significant electric vehicle use; and increasing the awareness and acceptance of electric vehicles. This report covers Program activities from 1992 to 1996. The Site Operator Program ended in September 1996, when it was superseded by the Field Operations Program. Electric vehicle testing included baseline performance testing, which was performed in conjunction with EV America. The baseline performance parameters included acceleration, braking, range, energy efficiency, and charging time. The Program collected fleet operations data on electric vehicles operated by the Program`s thirteen partners, comprising electric utilities, universities, and federal agencies. The Program`s partners had over 250 electric vehicles, from vehicle converters and original equipment manufacturers, in their operating fleets. Test results are available via the World Wide Web site at http://ev.inel.gov/sop.

  4. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Mexican Hat, Utah: Appendix D. Final report

    SciTech Connect

    1988-07-01

    This appendix is an assessment of the present conditions of the inactive uranium mill site near Mexican Hat, Utah. It consolidates available engineering, radiological, geotechnical, hydrological, meteorological, and other information pertinent to the design of the Remedial Action Plan. Plan is to characterize the conditions at the mill and tailings site so that the Remedial Action Contractor may complete final designs of the remedial action.

  5. Identification of putative active site residues of ACAT enzymes.

    PubMed

    Das, Akash; Davis, Matthew A; Rudel, Lawrence L

    2008-08-01

    In this report, we sought to determine the putative active site residues of ACAT enzymes. For experimental purposes, a particular region of the C-terminal end of the ACAT protein was selected as the putative active site domain due to its high degree of sequence conservation from yeast to humans. Because ACAT enzymes have an intrinsic thioesterase activity, we hypothesized that by analogy with the thioesterase domain of fatty acid synthase, the active site of ACAT enzymes may comprise a catalytic triad of ser-his-asp (S-H-D) amino acid residues. Mutagenesis studies revealed that in ACAT1, S456, H460, and D400 were essential for activity. In ACAT2, H438 was required for enzymatic activity. However, mutation of D378 destabilized the enzyme. Surprisingly, we were unable to identify any S mutations of ACAT2 that abolished catalytic activity. Moreover, ACAT2 was insensitive to serine-modifying reagents, whereas ACAT1 was not. Further studies indicated that tyrosine residues may be important for ACAT activity. Mutational analysis showed that the tyrosine residue of the highly conserved FYXDWWN motif was important for ACAT activity. Furthermore, Y518 was necessary for ACAT1 activity, whereas the analogous residue in ACAT2, Y496, was not. The available data suggest that the amino acid requirement for ACAT activity may be different for the two ACAT isozymes.

  6. Methanopyrus kandleri topoisomerase V contains three distinct AP lyase active sites in addition to the topoisomerase active site

    PubMed Central

    Rajan, Rakhi; Osterman, Amy; Mondragón, Alfonso

    2016-01-01

    Topoisomerase V (Topo-V) is the only topoisomerase with both topoisomerase and DNA repair activities. The topoisomerase activity is conferred by a small alpha-helical domain, whereas the AP lyase activity is found in a region formed by 12 tandem helix-hairpin-helix ((HhH)2) domains. Although it was known that Topo-V has multiple repair sites, only one had been mapped. Here, we show that Topo-V has three AP lyase sites. The atomic structure and Small Angle X-ray Scattering studies of a 97 kDa fragment spanning the topoisomerase and 10 (HhH)2 domains reveal that the (HhH)2 domains extend away from the topoisomerase domain. A combination of biochemical and structural observations allow the mapping of the second repair site to the junction of the 9th and 10th (HhH)2 domains. The second site is structurally similar to the first one and to the sites found in other AP lyases. The 3rd AP lyase site is located in the 12th (HhH)2 domain. The results show that Topo-V is an unusual protein: it is the only known protein with more than one (HhH)2 domain, the only known topoisomerase with dual activities and is also unique by having three AP lyase repair sites in the same polypeptide. PMID:26908655

  7. Methanopyrus kandleri topoisomerase V contains three distinct AP lyase active sites in addition to the topoisomerase active site.

    PubMed

    Rajan, Rakhi; Osterman, Amy; Mondragón, Alfonso

    2016-04-20

    Topoisomerase V (Topo-V) is the only topoisomerase with both topoisomerase and DNA repair activities. The topoisomerase activity is conferred by a small alpha-helical domain, whereas the AP lyase activity is found in a region formed by 12 tandem helix-hairpin-helix ((HhH)2) domains. Although it was known that Topo-V has multiple repair sites, only one had been mapped. Here, we show that Topo-V has three AP lyase sites. The atomic structure and Small Angle X-ray Scattering studies of a 97 kDa fragment spanning the topoisomerase and 10 (HhH)2 domains reveal that the (HhH)2 domains extend away from the topoisomerase domain. A combination of biochemical and structural observations allow the mapping of the second repair site to the junction of the 9th and 10th (HhH)2 domains. The second site is structurally similar to the first one and to the sites found in other AP lyases. The 3rd AP lyase site is located in the 12th (HhH)2 domain. The results show that Topo-V is an unusual protein: it is the only known protein with more than one (HhH)2 domain, the only known topoisomerase with dual activities and is also unique by having three AP lyase repair sites in the same polypeptide.

  8. Remedial action plan and site conceptual design for stabilization of the inactive uranium mill tailings sites at Rifle, Colorado. Appendix D, Final report

    SciTech Connect

    1992-02-01

    This appendix assesses the present conditions and data gathered about the two designated inactive uranium mill tailings sites near Rifle, Colorado, and the proposed disposal site six miles north of Rifle in the area of Estes Gulch. It consolidates available engineering, radiological, geotechnical, hydrological, meteorological, and other information pertinent to the design of the Remedial Action Plan (RAP). The data characterize conditions at the mill, tailings, and disposal site so that the Remedial Action Contractor (RAC) may complete final designs for the remedial actions.

  9. Extreme 3D reconstruction of the final ROSETTA/PHILAE landing site

    NASA Astrophysics Data System (ADS)

    Capanna, Claire; Jorda, Laurent; Lamy, Philippe; Gesquiere, Gilles; Delmas, Cédric; Durand, Joelle; Garmier, Romain; Gaudon, Philippe; Jurado, Eric

    2016-04-01

    The Philae lander aboard the Rosetta spacecraft successfully landed at the surface of comet 67P/Churyumov-Gerasimenko (hereafter 67P/C-G) after two rebounds on November 12, 2014. The final landing site, now known as « Abydos », has been identified on images acquired by the OSIRIS imaging system onboard the Rosetta orbiter[1]. The available images of Abydos are very limited in number and reveal a very extreme topography containing cliffs and overhangs. Furthermore, the surface is only observed under very high incidence angles of 60° on average, which implies that the images also exhibit lots of cast shadows. This makes it very difficult to reconstruct the 3D topography with standard methods such as photogrammetry or standard clinometry. We apply a new method called ''Multiresolution PhotoClinometry by Deformation'' (MPCD, [2]) to retrieve the 3D topography of the area around Abydos. The method works in two main steps: (i) a DTM of this region is extracted from a low resolution MPCD global shape model of comet 67P/C-G, and (ii) the resulting triangular mesh is progressively deformed at increasing spatial sampling down to 0.25 m in order to match a set of 14 images of Abydos with projected pixel scales between 1 and 8 m. The method used to perform the image matching is a quasi-Newton non-linear optimization method called L-BFGS-b[3] especially suited to large-scale problems. Finally, we also checked the compatibility of the final MPCD digital terrain model with a set of five panoramic images obtained by the CIVA-P instrument aboard Philae[4]. [1] Lamy et al., 2016, submitted. [2] Capanna et al., Three dimensional reconstruction using multiresoluton photoclinometry by deformation, The visual Computer, v. 29(6-8) pp. 825-835, 2013. [3] Morales et al., Remark on "Algorithm 778: L-BFGS-B: Fortran subroutines for large-scale bound constrained optimization", v.38(1) pp.1-4, ACM Trans. Math. Softw., 2011 [4] Bibring et al., 67P/Churyumov-Gerasimenko surface properties as

  10. Final report for the geothermal well site restoration and plug and abandonment of wells: DOE Pleasant Bayou test site, Brazoria County, Texas

    SciTech Connect

    Rinehart, Ben N.; Seigel, Ben H.

    1994-03-13

    For a variety of reasons, thousands of oil and gas wells have been abandoned in the Gulf Coast Region of the United States. Many of these wells penetrated geopressured zones whose resource potential for power generation was undervalued or ignored. The U.S. Department of Energy (DOE) Geopressured-Geothermal Research Program was chartered to improve geothermal technology to the point where electricity could be commercially produced from a substantial number of geopressured resource sites. This research program focused on relatively narrow technical issues that are unique to geopressured resources such as the ability to predict reservoir production capacity based on preliminary flow tests. Three well sites were selected for the research program. These are the Willis Hulin and Gladys McCall sites in Louisiana, and the Pleasant Bayou site in Texas. The final phase of this research project consists of plug and abandonment (P&A) of the wells and site restoration.

  11. Promoter-proximal polyadenylation sites reduce transcription activity

    PubMed Central

    Andersen, Pia K.; Lykke-Andersen, Søren; Jensen, Torben Heick

    2012-01-01

    Gene expression relies on the functional communication between mRNA processing and transcription. We previously described the negative impact of a point-mutated splice donor (SD) site on transcription. Here we demonstrate that this mutation activates an upstream cryptic polyadenylation (CpA) site, which in turn causes reduced transcription. Functional depletion of U1 snRNP in the context of the wild-type SD triggers the same CpA event accompanied by decreased RNA levels. Thus, in accordance with recent findings, U1 snRNP can shield premature pA sites. The negative impact of unshielded pA sites on transcription requires promoter proximity, as demonstrated using artificial constructs and supported by a genome-wide data set. Importantly, transcription down-regulation can be recapitulated in a gene context devoid of splice sites by placing a functional bona fide pA site/transcription terminator within ∼500 base pairs of the promoter. In contrast, promoter-proximal positioning of a pA site-independent histone gene terminator supports high transcription levels. We propose that optimal communication between a pA site-dependent gene terminator and its promoter critically depends on gene length and that short RNA polymerase II-transcribed genes use specialized termination mechanisms to maintain high transcription levels. PMID:23028143

  12. Active chemisorption sites in functionalized ionic liquids for carbon capture.

    PubMed

    Cui, Guokai; Wang, Jianji; Zhang, Suojiang

    2016-07-25

    Development of novel technologies for the efficient and reversible capture of CO2 is highly desired. In the last decade, CO2 capture using ionic liquids has attracted intensive attention from both academia and industry, and has been recognized as a very promising technology. Recently, a new approach has been developed for highly efficient capture of CO2 by site-containing ionic liquids through chemical interaction. This perspective review focuses on the recent advances in the chemical absorption of CO2 using site-containing ionic liquids, such as amino-based ionic liquids, azolate ionic liquids, phenolate ionic liquids, dual-functionalized ionic liquids, pyridine-containing ionic liquids and so on. Other site-containing liquid absorbents such as amine-based solutions, switchable solvents, and functionalized ionic liquid-amine blends are also investigated. Strategies have been discussed for how to activate the existent reactive sites and develop novel reactive sites by physical and chemical methods to enhance CO2 absorption capacity and reduce absorption enthalpy. The carbon capture mechanisms of these site-containing liquid absorbents are also presented. Particular attention has been paid to the latest progress in CO2 capture in multiple-site interactions by amino-free anion-functionalized ionic liquids. In the last section, future directions and prospects for carbon capture by site-containing ionic liquids are outlined.

  13. Active Sites Environmental Monitoring Program: Mid-FY 1991 report

    SciTech Connect

    Ashwood, T.L.; Wickliff, D.S.; Morrissey, C.M.

    1991-10-01

    This report summarizes the activities of the Active Sites Environmental Monitoring Program (ASEMP) from October 1990 through March 1991. The ASEMP was established in 1989 by Solid Waste Operations and the Environmental Sciences Division to provide early detection and performance monitoring at active low-level radioactive waste (LLW) disposal sites in Solid Waste Storage Area (SWSA) 6 and transuranic (TRU) waste storage sites in SWSA 5 as required by chapters II and III of US Department of Energy Order 5820.2A. Monitoring results continue to demonstrate the no LLW is being leached from the storage vaults on the tumulus pads. Loading of vaults on Tumulus II began during this reporting period and 115 vaults had been loaded by the end of March 1991.

  14. Post-Injection Geophysical Evaluation of the Winding Ridge Site CRADA 98-F012, Final Report

    SciTech Connect

    Connie Lyons; Richard Current; Terry Ackman

    1998-09-16

    Acid mine drainage (AMD) from underground mines is a major environmental problem. The disposal of coal combustion by-products (CCB) is also a major national problem due to the large volumes produced annually and the economics associated with transportation and environmentally safe disposal. The concept of returning large volumes of the CCB to their point of origin, underground mines, and using the typically alkaline and pozzolanic attributes of the waste material for the remediation of AMD has been researched rather diligently during the past few years by various federal and state agencies and universities. As the result, the State of Maryland initiated a full-scale demonstration of this concept in a small, 5-acre, unmapped underground mine located near Friendsville, MD. Through a cooperative agreement between the State of Maryland and the U.S. Department of Energy, several geophysical techniques were evaluated as potential tools for the post-injection evaluation of the underground mine site. Three non-intrusive geophysical surveys, two electromagnetic (EM) techniques and magnetometry, were conducted over the Frazee Mine, which is located on Winding Ridge near Friendsville, MD. The EM surveys were conducted to locate ground water in both mine void and overburden. The presence of magnetite, which is naturally inherent to CCB'S due to the combustion process and essentially transparent in sedimentary rock, provided the reason for using magnetometry to locate the final resting place of the CCB grout.

  15. Final contamination assessment report, site 4-6, motor pool area. Version 3. 1. 19

    SciTech Connect

    Not Available

    1988-07-01

    This final report documents the phase I contamination survey of site 4-6, a vehicle maintenance area. A total of 36 borings, 1 soil grab sample, and 3 water samples yielded 169 samples. These samples were analyzed for volatile and semivolatile organics and metals. The following analytes were detected within or above their respective indicator ranges: C6H6, CHCl3, 11DClE, ETC6H6, CH2Cl2, TClEE, MEC6H5, 111TCE, TRClE, XYLEN, ALDRN, DBCP, CD, Cr, Cu, Pb, Zn, As, and Hg. Because the phase I survey has defined the general extent of potential contamination, no phase II program is planned at this time. However, ground water monitoring and the drilling of a limited number of borings near the fuel storage tanks are recommended. The volume of potentially contaminated material presented is estimated at 180,000 cubic yards. Appendices include chemical names, phase I chemical data, and comments and responses.

  16. Persistence of biologically active compounds in aquatic systems: Final report

    SciTech Connect

    Boelter, A.M.; Fernandez, J.D.; Meyer, J.S.; Sanchez, D.A.; Bergman, H.L.

    1986-11-01

    Waters collected from two study sites were tested for persistence of biologically active compounds as the waters percolated through experimental media. At the first site, the Paraho Lysimeter in Anvil Points, Colorado, two leachate samples (early and late flow in Spring 1983) were collected from each of four piles of processed oil shale overlain by different thicknesses of soil. Although water quality differed among samples, six of eight lysimeter leachates tested were acutely toxic to an aquatic invertebrate, Daphnia magna, and five were acutely toxic to fathead minnows (Pimephales promelas). Water collected from a modified in situ (MIS) retort was percolated through columns containing three different types of soil. Raw leachate from the MIS spent shale was acutely toxic to an aquatic invertebrate, Ceriodaphnia dubia. The toxicity of samples from nine pore volumes of retort water percolating through a column containing a sandy soil increased with successive pore volumes, but leachate toxicity never equaled the toxicity of the retort water. In contrast, the first pore volumes of retort water or reconstituted water leached through a sandy loam soil were more toxic than the retort water; however, the second pore volumes of leachates were not toxic. First pore volume leachates of retort water percolating through a sandy clay loam soil were much less toxic than the retort water; second pore volume leachates were not toxic.

  17. Active harmonic filter technology and market assessment. Final report

    SciTech Connect

    Bhattacharya, S.; Divan, D.; Sutherland, P.

    1998-08-01

    Non-linear loads such as three-phase rectifiers, adjustable speed drives (ASDs), and arcing loads can cause voltage distortion and other power quality problems due to their interaction with the power grid. This report provides a technical and marketing assessment of active harmonic filters, a promising approach to preventing these problems at their source. Although predicting the direction and magnitude of harmonic currents is difficult due to highly interconnected nature of distribution systems, even small harmonic producing loads can result in high levels of harmonic current flow between the utility and a customer and can also cause a resonance problem at sites far removed from the harmonic producing load. The best way to keep voltage distortion low in a utility system is to constrain the harmonic currents at their sources. However, since regulation of harmonic pollution does not provide any additional value to the customer, it is unlikely that any controls will be implemented on a consistent basis in the absence of mandatory requirements. In the United States, a step toward a standard operating practice is the IEEE 519-1992 recommended harmonic standard that provides guidelines for limiting harmonic currents by industrial plants. This report identifies the equipment likely to produce harmonic loads and explains the kinds of problems that harmonic currents can cause in a utility distribution system. It describes possible solutions to these problems, including harmonic filtering and other technologies. The report examines the prospects for wider use of active harmonic filter technology and discusses the important marketing issues for potential active filter marketers and manufacturers, such as the barriers to and drivers of increased use of active filter technology and the price points for active filters.

  18. Final Report: Results of Environmental Site Investigation at Sylvan Grove, Kansas

    SciTech Connect

    LaFreniere, Lorraine M

    2014-09-01

    Sylvan Grove is located in western Lincoln County, approximately 60 mi west of Salina, Kansas (Figure 1.1). From 1954 to 1966, the Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), operated a grain storage facility at the northeastern edge of Sylvan Grove. During this time, commercial grain fumigants containing carbon tetrachloride were in common use to preserve grain in storage. In 1998, the Kansas Department of Health and Environment (KDHE) found carbon tetrachloride above the maximum contaminant level (MCL) of 5 μg/L in groundwater from one private well used for livestock and lawn and garden watering. The 1998 KDHE sampling at Sylvan Grove was conducted under the USDA private well sampling program. To determine whether the former CCC/USDA facility at Sylvan Grove is a potential contaminant source and its possible relationship to the contamination in groundwater, the CCC/USDA proposed to conduct an environmental site investigation, in accordance with the Intergovernmental Agreement between the KDHE and the Farm Service Agency (FSA) of the USDA. Argonne National Laboratory, on behalf of the CCC/USDA, developed a work plan (Argonne 2012) for the site investigation and a supplemental work plan for indoor and ambient air sampling (Appendix A). The proposed work was approved by the KDHE (2012a, 2013). The investigations were performed by the Environmental Science Division of Argonne National Laboratory, on behalf of the CCC/USDA. The main activities for the site investigation were conducted in June 2012, and indoor and ambient air sampling was performed in February 2013. This report presents the findings of the investigations at Sylvan Grove.

  19. Final Status Survey Report for Corrective Action Unit 117 - Pluto Disassembly Facility, Building 2201, Nevada National Security Site, Nevada

    SciTech Connect

    Jeremy Gwin and Douglas Frenette

    2010-09-30

    This document contains the process knowledge, radiological data and subsequent statistical methodology and analysis to support approval for the radiological release of Corrective Action Unit (CAU) 117 – Pluto Disassembly Facility, Building 2201 located in Area 26 of the Nevada National Security Site (NNSS). Preparations for release of the building began in 2009 and followed the methodology described in the Multi-Agency Radiation Survey and Site Investigation Manual (MARSSIM). MARSSIM is the DOE approved process for release of Real Property (buildings and landmasses) to a set of established criteria or authorized limits. The pre-approved authorized limits for surface contamination values and corresponding assumptions were established by DOE O 5400.5. The release criteria coincide with the acceptance criteria of the U10C landfill permit. The U10C landfill is the proposed location to dispose of the radiologically non-impacted, or “clean,” building rubble following demolition. However, other disposition options that include the building and/or waste remaining at the NNSS may be considered providing that the same release limits apply. The Final Status Survey was designed following MARSSIM guidance by reviewing historical documentation and radiological survey data. Following this review a formal radiological characterization survey was performed in two phases. The characterization revealed multiple areas of residual radioactivity above the release criteria. These locations were remediated (decontaminated) and then the surface activity was verified to be less than the release criteria. Once remediation efforts had been successfully completed, a Final Status Survey Plan (10-015, “Final Status Survey Plan for Corrective Action Unit 117 – Pluto Disassembly Facility, Building 2201”) was developed and implemented to complete the final step in the MARSSIM process, the Final Status Survey. The Final Status Survey Plan consisted of categorizing each individual room

  20. BAX Activation is Initiated at a Novel Interaction Site

    PubMed Central

    Gavathiotis, Evripidis; Suzuki, Motoshi; Davis, Marguerite L.; Pitter, Kenneth; Bird, Gregory H.; Katz, Samuel G.; Tu, Ho-Chou; Kim, Hyungjin; Cheng, Emily H.-Y.; Tjandra, Nico; Walensky, Loren D.

    2008-01-01

    BAX is a pro-apoptotic protein of the BCL-2 family stationed in the cytosol until activated by a diversity of stress stimuli to induce cell death. Anti-apoptotic proteins such as BCL-2 counteract BAX-mediated cell death. Although an interaction site that confers survival functionality has been defined for anti-apoptotic proteins, an activation site has not been identified for BAX, rendering its explicit trigger mechanism unknown. We previously developed Stabilized Alpha-Helix of BCL-2 domains (SAHBs) that directly initiate BAX-mediated mitochondrial apoptosis. Here we demonstrate by NMR analysis that BIM SAHB binds BAX at an interaction site that is distinct from the canonical binding groove characterized for anti-apoptotic proteins. The specificity of the BIM SAHB-BAX interaction is highlighted by point mutagenesis that abrogates functional activity, confirming that BAX activation is initiated at this novel structural location. Thus, we have now defined a BAX interaction site for direct activation, establishing a new target for therapeutic modulation of apoptosis. PMID:18948948

  1. Redd Site Selection and Spawning Habitat Use by Fall Chinook Salmon, Hanford Reach, Columbia River : Final Report 1995 - 1998.

    SciTech Connect

    Geist, David R.

    1999-05-01

    This report summarizes results of research activities conducted from 1995 through 1998 on identifying the spawning habitat requirements of fall chinook salmon (Oncorhynchus tshawytscha) in the Hanford Reach of the Columbia River. The project investigated whether traditional spawning habitat models could be improved in order to make better predictions of available habitat for fall chinook salmon in the Snake River. Results suggest models could be improved if they used spawning area-specific, rather than river-specific, spawning characteristics; incorporated hyporheic discharge measurements; and gave further consideration to the geomorphic features that are present in the unconstrained segments of large alluvial rivers. Ultimately the recovery of endangered fall chinook salmon will depend on how well we are able to recreate the characteristics once common in alluvial floodplains of large rivers. The results from this research can be used to better define the relationship between these physical habitat characteristics and fall chinook salmon spawning site selection, and provide more efficient use of limited recovery resources. This report is divided into four chapters which were presented in the author's doctoral dissertation which he completed through the Department of Fisheries and Wildlife at Oregon State University. Each of the chapters has been published in peer reviewed journals or is currently under review. Chapter one is a conceptual spawning habitat model that describes how geomorphic features of river channels create hydraulic processes, including hyporheic flows, that influence where salmon spawn in unconstrained reaches of large mainstem alluvial rivers. Chapter two describes the comparison of the physical factors associated with fall chinook salmon redd clusters located at two sites within the Reach. Spatial point pattern analysis of redds showed that redd clusters averaged approximately 10 hectares in area and their locations were consistent from year to

  2. Involvement of novel autophosphorylation sites in ATM activation.

    PubMed

    Kozlov, Sergei V; Graham, Mark E; Peng, Cheng; Chen, Philip; Robinson, Phillip J; Lavin, Martin F

    2006-08-09

    ATM kinase plays a central role in signaling DNA double-strand breaks to cell cycle checkpoints and to the DNA repair machinery. Although the exact mechanism of ATM activation remains unknown, efficient activation requires the Mre11 complex, autophosphorylation on S1981 and the involvement of protein phosphatases and acetylases. We report here the identification of several additional phosphorylation sites on ATM in response to DNA damage, including autophosphorylation on pS367 and pS1893. ATM autophosphorylates all these sites in vitro in response to DNA damage. Antibodies against phosphoserine 1893 revealed rapid and persistent phosphorylation at this site after in vivo activation of ATM kinase by ionizing radiation, paralleling that observed for S1981 phosphorylation. Phosphorylation was dependent on functional ATM and on the Mre11 complex. All three autophosphorylation sites are physiologically important parts of the DNA damage response, as phosphorylation site mutants (S367A, S1893A and S1981A) were each defective in ATM signaling in vivo and each failed to correct radiosensitivity, genome instability and cell cycle checkpoint defects in ataxia-telangiectasia cells. We conclude that there are at least three functionally important radiation-induced autophosphorylation events in ATM.

  3. Resonant active sites in catalytic ammonia synthesis: A structural model

    NASA Astrophysics Data System (ADS)

    Cholach, Alexander R.; Bryliakova, Anna A.; Matveev, Andrey V.; Bulgakov, Nikolai N.

    2016-03-01

    Adsorption sites Mn consisted of n adjacent atoms M, each bound to the adsorbed species, are considered within a realistic model. The sum of bonds Σ lost by atoms in a site in comparison with the bulk atoms was used for evaluation of the local surface imperfection, while the reaction enthalpy at that site was used as a measure of activity. The comparative study of Mn sites (n = 1-5) at basal planes of Pt, Rh, Ir, Fe, Re and Ru with respect to heat of N2 dissociative adsorption QN and heat of Nad + Had → NHad reaction QNH was performed using semi-empirical calculations. Linear QN(Σ) increase and QNH(Σ) decrease allowed to specify the resonant Σ for each surface in catalytic ammonia synthesis at equilibrium Nad coverage. Optimal Σ are realizable for Ru2, Re2 and Ir4 only, whereas other centers meet steric inhibition or unreal crystal structure. Relative activity of the most active sites in proportion 5.0 × 10- 5: 4.5 × 10- 3: 1: 2.5: 3.0: 1080: 2270 for a sequence of Pt4, Rh4, Fe4(fcc), Ir4, Fe2-5(bcc), Ru2, Re2, respectively, is in agreement with relevant experimental data. Similar approach can be applied to other adsorption or catalytic processes exhibiting structure sensitivity.

  4. Final expanded site inspection, ammunition storage area, Anniston Army Depot, Anniston, Alabama. Final report, September 1992-November 1994

    SciTech Connect

    Suomela, K.D.; Highsmith, R.L.; Rapuano, K.F.; Kirchner, B.

    1994-11-15

    An Expanded Site Inspection (ESI) was conducted at the Anniston Army Depot (ANAD) Ammunition Storage Area (ASA). The objective of this ESI was to gather the information and data necessary to determine whether there is sufficient evidence of any release of contamination that would require additional investigation. The ASA contains 1,300 ammunition storage magazines and an ammunition maintenance workshop complex which includes buildings for maintenance, demilitarization, and inspection of all types of ammunition and their components. Fifteen Solid Waste Management Units (SWMUs) were the focus of the ESI, of which 11 were recommend for further investigation. The work included a review of historical records, field investigations, laboratory analyses, data interpretation, and report preparation. Contamination from volatile organic compounds and semi volatile organic compounds is not a major problem at the ASA. Arsenic, beryllium, cadmium, chromium, lead, mercury, nickel, silver, vanadium, zinc, explosives, and total petroleum hydrocarbons were detected above control screening values levels in one or more of the media sampled. Nitrate/nitrite and total organic carbon were also detected above control screening values in samples of groundwater, soil, and sediment from a number of SWMUs.

  5. Chemical Modification of Papain and Subtilisin: An Active Site Comparison

    ERIC Educational Resources Information Center

    St-Vincent, Mireille; Dickman, Michael

    2004-01-01

    An experiment using methyle methanethiosulfonate (MMTS) and phenylmethylsulfonyl flouride (PMSF) to specifically modify the cysteine and serine residues in the active sites of papain and subtilism respectively is demonstrated. The covalent modification of these enzymes and subsequent rescue of papain shows the beginning biochemist that proteins…

  6. Spectroscopic studies of the active site of galactose oxidase

    SciTech Connect

    Knowles, P.F.; Brown, R.D. III; Koenig, S.H.

    1995-07-19

    X-ray absorption and EPR spectroscopy have been used to probe the copper site structure in galactose oxidase at pH 4.5 and 7.0. the results suggest that there are no major differences in the structure of the tetragonal Cu(II) site at these pH values. Analysis of the extended X-ray absorption fine structure (EXAFS) indicates that four N,O scatterers are present at approximately 2 {Angstrom}; these are presumably the equatorial ligands. In addition, the EXAFS data establish that oxidative activation to produce the active-site tyrosine radical does not cause major changes in the copper coordination environment. Therefore results obtained on the one-electron reduced enzyme, containing Cu(II) but not the tyrosine radical, probably also apply to the catalytically active Cu(II)/tyrosine radical state. Solvent water exchange, inhibitor binding, and substrate binding have been probed via nuclear magnetic relaxation dispersion (NMRD) measurements. The NMRD profile of galactose oxidase is quantitatively consistent with the rapid exchange of a single, equatorial water ligand with a Cu(II)-O separation of about 2.4 {Angstrom}. Azide and cyanide displace this coordinated water. The binding of azide and the substrate dihydroxyacetone produce very similar effects on the NMRD profile of galactose oxidase, indicating that substrates also bind to the active site Cu(II) in an equatorial position.

  7. Energy transfer at the active sites of heme proteins

    SciTech Connect

    Dlott, D.D.; Hill, J.R.

    1995-12-31

    Experiments using a picosecond pump-probe apparatus at the Picosecond Free-electron Laser Center at Stanford University, were performed to investigate the relaxation of carbon monoxide bound to the active sites of heme proteins. The significance of these experiments is two-fold: (1) they provide detailed information about molecular dynamics occurring at the active sites of proteins; and (2) they provide insight into the nature of vibrational relaxation processes in condensed matter. Molecular engineering is used to construct various molecular systems which are studied with the FEL. We have studied native proteins, mainly myoglobin obtained from different species, mutant proteins produced by genetic engineering using recombinant DNA techniques, and a variety of model systems which mimic the structures of the active sites of native proteins, which are produced using molecular synthesis. Use of these different systems permits us to investigate how specific molecular structural changes affect dynamical processes occurring at the active sites. This research provides insight into the problems of how different species needs are fulfilled by heme proteins which have greatly different functionality, which is induced by rather small structural changes.

  8. Field Performance of A Compacted Clay Landfill Final cover At A Humid Site

    SciTech Connect

    Albright, William H.; Benson, Craig H.; Gee, Glendon W.; Abichou, Tarek; Mcdonald, Eric V.; Tyler, Scott W.; Rock, Steven

    2006-11-01

    A study was conducted in southern Georgia, USA to evaluate how the hydraulic properties of the compacted clay barrier layer in a landfill final cover changed over a 4-yr service life. The cover was part of a test section constructed in a large drainage lysimeter that allowed CE Database subject headings: landfill, hydrogeology, compacted soils, lysimeters, desiccation continuous monitoring of the water balance. Patterns in the drainage (i.e., flow from the bottom of the cover) record suggest that preferential flow paths developed in the clay barrier soon after construction, apparently in response to desiccation cracking. After four years, the clay barrier was excavated and examined for changes in soil structure and hydraulic conductivity. Tests were conducted in situ with a sealed double-ring infiltrometer and two-stage borehole permeameters and in the laboratory on hand-carved blocks taken during construction and after four years of service. The in situ and laboratory tests indicated that the hydraulic conductivity increased approximately three orders of magnitude (from ? 10-7 to ? 10-4 cm s-1) during the service life. A dye tracer test and soil structure analysis showed that extensive cracking and root development occurred throughout the entire depth of the barrier layer. Laboratory tests on undisturbed specimens of the clay barrier indicated that the hydraulic conductivity of damaged clay barriers can be under-estimated significantly if small specimens (e.g., tube samples) are used for hydraulic conductivity assessment. The findings also indicate that clay barriers must be protected from desiccation and root intrusion if they are expected to function as intended, even at sites in warm, humid locations.

  9. EPA Finalizes Cleanup Plan for the Nuclear Metals Site in Concord, Mass.

    EPA Pesticide Factsheets

    EPA has completed the Record of Decision (ROD) for the Nuclear Metals, Inc. Superfund Site, located in Concord, Mass. The ROD outlines a detailed plan for cleaning up contaminated soil, sediment and groundwater at the Site.

  10. Evaluation of Final Radiological Conditions at Areas of the Niagara Falls Storage Site Remediated under the Formerly Utilized Sites Remedial Action Program -12184

    SciTech Connect

    Clayton, Christopher; Kothari, Vijendra; Starr, Ken; Widdop, Michael; Gillespie, Joey

    2012-02-26

    The U. S. Department of Energy (DOE) methods and protocols allow evaluation of remediation and final site conditions to determine if remediated sites remain protective. Two case studies are presented that involve the Niagara Falls Storage Site (NFSS) and associated vicinity properties (VPs), which are being remediated under the Formerly Utilized Sites Remedial Action Program (FUSRAP). These properties are a part of the former Lake Ontario Ordnance Works (LOOW). In response to stakeholders concerns about whether certain remediated NFSS VPs were putting them at risk, DOE met with stakeholders and agreed to evaluate protectiveness. Documentation in the DOE records collection adequately described assessed and final radiological conditions at the completed VPs. All FUSRAP wastes at the completed sites were cleaned up to meet DOE guidelines for unrestricted use. DOE compiled the results of the investigation in a report that was released for public comment. In conducting the review of site conditions, DOE found that stakeholders were also concerned about waste from the Separations Process Research Unit (SPRU) at the Knolls Atomic Power Laboratory (KAPL) that was handled at LOOW. DOE agreed to determine if SPRU waste remained at that needed to be remediated. DOE reviewed records of waste characterization, historical handling locations and methods, and assessment and remediation data. DOE concluded that the SPRU waste was remediated on the LOOW to levels that pose no unacceptable risk and allow unrestricted use and unlimited exposure. This work confirms the following points as tenets of an effective long-term surveillance and maintenance (LTS&M) program: Stakeholder interaction must be open and transparent, and DOE must respond promptly to stakeholder concerns. DOE, as the long-term custodian, must collect and preserve site records in order to demonstrate that remediated sites pose no unacceptable risk. DOE must continue to maintain constructive relationships with the U

  11. Activation of phenylalanine hydroxylase by phenylalanine does not require binding in the active site.

    PubMed

    Roberts, Kenneth M; Khan, Crystal A; Hinck, Cynthia S; Fitzpatrick, Paul F

    2014-12-16

    Phenylalanine hydroxylase (PheH), a liver enzyme that catalyzes the hydroxylation of excess phenylalanine in the diet to tyrosine, is activated by phenylalanine. The lack of activity at low levels of phenylalanine has been attributed to the N-terminus of the protein's regulatory domain acting as an inhibitory peptide by blocking substrate access to the active site. The location of the site at which phenylalanine binds to activate the enzyme is unknown, and both the active site in the catalytic domain and a separate site in the N-terminal regulatory domain have been proposed. Binding of catecholamines to the active-site iron was used to probe the accessibility of the active site. Removal of the regulatory domain increases the rate constants for association of several catecholamines with the wild-type enzyme by ∼2-fold. Binding of phenylalanine in the active site is effectively abolished by mutating the active-site residue Arg270 to lysine. The k(cat)/K(phe) value is down 10⁴ for the mutant enzyme, and the K(m) value for phenylalanine for the mutant enzyme is >0.5 M. Incubation of the R270K enzyme with phenylalanine also results in a 2-fold increase in the rate constants for catecholamine binding. The change in the tryptophan fluorescence emission spectrum seen in the wild-type enzyme upon activation by phenylalanine is also seen with the R270K mutant enzyme in the presence of phenylalanine. Both results establish that activation of PheH by phenylalanine does not require binding of the amino acid in the active site. This is consistent with a separate allosteric site, likely in the regulatory domain.

  12. Changes in active site histidine hydrogen bonding trigger cryptochrome activation.

    PubMed

    Ganguly, Abir; Manahan, Craig C; Top, Deniz; Yee, Estella F; Lin, Changfan; Young, Michael W; Thiel, Walter; Crane, Brian R

    2016-09-06

    Cryptochrome (CRY) is the principal light sensor of the insect circadian clock. Photoreduction of the Drosophila CRY (dCRY) flavin cofactor to the anionic semiquinone (ASQ) restructures a C-terminal tail helix (CTT) that otherwise inhibits interactions with targets that include the clock protein Timeless (TIM). All-atom molecular dynamics (MD) simulations indicate that flavin reduction destabilizes the CTT, which undergoes large-scale conformational changes (the CTT release) on short (25 ns) timescales. The CTT release correlates with the conformation and protonation state of conserved His378, which resides between the CTT and the flavin cofactor. Poisson-Boltzmann calculations indicate that flavin reduction substantially increases the His378 pKa Consistent with coupling between ASQ formation and His378 protonation, dCRY displays reduced photoreduction rates with increasing pH; however, His378Asn/Arg variants show no such pH dependence. Replica-exchange MD simulations also support CTT release mediated by changes in His378 hydrogen bonding and verify other responsive regions of the protein previously identified by proteolytic sensitivity assays. His378 dCRY variants show varying abilities to light-activate TIM and undergo self-degradation in cellular assays. Surprisingly, His378Arg/Lys variants do not degrade in light despite maintaining reactivity toward TIM, thereby implicating different conformational responses in these two functions. Thus, the dCRY photosensory mechanism involves flavin photoreduction coupled to protonation of His378, whose perturbed hydrogen-bonding pattern alters the CTT and surrounding regions.

  13. Changes in active site histidine hydrogen bonding trigger cryptochrome activation

    PubMed Central

    Ganguly, Abir; Manahan, Craig C.; Top, Deniz; Yee, Estella F.; Lin, Changfan; Young, Michael W.; Thiel, Walter; Crane, Brian R.

    2016-01-01

    Cryptochrome (CRY) is the principal light sensor of the insect circadian clock. Photoreduction of the Drosophila CRY (dCRY) flavin cofactor to the anionic semiquinone (ASQ) restructures a C-terminal tail helix (CTT) that otherwise inhibits interactions with targets that include the clock protein Timeless (TIM). All-atom molecular dynamics (MD) simulations indicate that flavin reduction destabilizes the CTT, which undergoes large-scale conformational changes (the CTT release) on short (25 ns) timescales. The CTT release correlates with the conformation and protonation state of conserved His378, which resides between the CTT and the flavin cofactor. Poisson-Boltzmann calculations indicate that flavin reduction substantially increases the His378 pKa. Consistent with coupling between ASQ formation and His378 protonation, dCRY displays reduced photoreduction rates with increasing pH; however, His378Asn/Arg variants show no such pH dependence. Replica-exchange MD simulations also support CTT release mediated by changes in His378 hydrogen bonding and verify other responsive regions of the protein previously identified by proteolytic sensitivity assays. His378 dCRY variants show varying abilities to light-activate TIM and undergo self-degradation in cellular assays. Surprisingly, His378Arg/Lys variants do not degrade in light despite maintaining reactivity toward TIM, thereby implicating different conformational responses in these two functions. Thus, the dCRY photosensory mechanism involves flavin photoreduction coupled to protonation of His378, whose perturbed hydrogen-bonding pattern alters the CTT and surrounding regions. PMID:27551082

  14. EPA Finalizes $4 Million Cleanup Plan for Fulton Avenue Superfund Site in Hempstead and North Hempstead, N.Y.

    EPA Pesticide Factsheets

    (New York, N.Y.) The U.S. Environmental Protection Agency has finalized its decision to modify an interim cleanup plan originally issued in 2007 to address a portion of the contaminated groundwater at the Fulton Avenue Superfund site in the Towns of North

  15. 10 CFR 2.629 - Finality of partial decision on site suitability issues in a combined license proceeding.

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ...), the Director of the Office of New Reactors or the Director of the Office of Nuclear Reactor Regulation... 10 Energy 1 2013-01-01 2013-01-01 false Finality of partial decision on site suitability issues in a combined license proceeding. 2.629 Section 2.629 Energy NUCLEAR REGULATORY COMMISSION AGENCY...

  16. 10 CFR 2.629 - Finality of partial decision on site suitability issues in a combined license proceeding.

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ...), the Director of the Office of New Reactors or the Director of the Office of Nuclear Reactor Regulation... 10 Energy 1 2014-01-01 2014-01-01 false Finality of partial decision on site suitability issues in a combined license proceeding. 2.629 Section 2.629 Energy NUCLEAR REGULATORY COMMISSION AGENCY...

  17. Probing the promiscuous active site of myo-inositol dehydrogenase using synthetic substrates, homology modeling, and active site modification.

    PubMed

    Daniellou, Richard; Zheng, Hongyan; Langill, David M; Sanders, David A R; Palmer, David R J

    2007-06-26

    The active site of myo-inositol dehydrogenase (IDH, EC 1.1.1.18) from Bacillus subtilis recognizes a variety of mono- and disaccharides, as well as 1l-4-O-substituted inositol derivatives. It catalyzes the NAD+-dependent oxidation of the axial alcohol of these substrates with comparable kinetic constants. We have found that 4-O-p-toluenesulfonyl-myo-inositol does not act as a substrate for IDH, in contrast to structurally similar compounds such as those bearing substituted benzyl substituents in the same position. X-ray crystallographic analysis of 4-O-p-toluenesulfonyl-myo-inositol and 4-O-(2-naphthyl)methyl-myo-inositol, which is a substrate for IDH, shows a distinct difference in the preferred conformation of the aryl substituent. Conformational analysis of known substrates of IDH suggests that this conformational difference may account for the difference in reactivity of 4-O-p-toluenesulfonyl-myo-inositol in the presence of IDH. A sequence alignment of IDH with the homologous glucose-fructose oxidoreductase allowed the construction of an homology model of inositol dehydrogenase, to which NADH and 4-O-benzyl-scyllo-inosose were docked and the active site energy minimized. The active site model is consistent with all experimental results and suggests that a conserved tyrosine-glycine-tyrosine motif forms the hydrophobic pocket adjoining the site of inositol recognition. Y233F and Y235F retain activity, while Y233R and Y235R do not. A histidine-aspartate pair, H176 and D172, are proposed to act as a dyad in which H176 is the active site acid/base. The enzyme is inactivated by diethyl pyrocarbonate, and the mutants H176A and D172N show a marked loss of activity. Kinetic isotope effect experiments with D172N indicate that chemistry is rate-determining for this mutant.

  18. The active site structure and mechanism of phosphoenolpyruvate utilizing enzymes

    SciTech Connect

    Cheng, K.C.

    1989-01-01

    Arginine specific reagents showed irreversible inhibition of avian liver mitochondrial phosphoenolpyruvate carboxykinase. Potent protection against modification was elicited by CO{sub 2} or CO{sub 2} in the presence of other substrates. Labeling of enzyme with (7-{sup 14}C) phenylglyoxal showed that 1 or 2 arginines are involved in CO{sub 2} binding and activation. Peptide map studies showed this active site arginine residues is located at position 289. Histidine specific reagents showed pseudo first order inhibition of avian mitochondrial phosphoenolpyruvate carboxykinase activity. The best protection against modification was elicited by IDP or IDP and Mn{sup +2}. One histidine residue is at or near the phosphoenolpyruvate binding site as demonstrated in the increased absorbance at 240 nm and proton relaxation rate studies. Circular dichroism studies reveal that enzyme structure was perturbed by diethylpyrocarbonate modification. Metal binding studies suggest that this enzyme has only one metal binding site. The putative binding sites from several GTP and phosphoenolpyruvate utilizing enzymes are observed in P-enolpyruvate carboxykinase from different species.

  19. Remedial action plan and site design for stabilization of the inactive uranium mill tailings sites at Slick Rock, Colorado. Attachment 3, Ground water hydrology report: Preliminary final

    SciTech Connect

    Not Available

    1994-03-04

    The US Environmental Protection Agency (EPA) has established health and environmental protection regulations to correct and prevent ground water contamination resulting from processing activities at inactive uranium milling sites (52 FR 36000 (1987)). According to the Uranium Mill Tailings Radiation Control Act (UMTRCA) of 1978, 42 USC {section}7901 et seq., the US Department of Energy (DOE) is responsible for assessing the inactive uranium processing sites. The DOE has determined that for Slick Rock, this assessment shall include hydrogeologic site characterization for two separate uranium processing sites, the Union Carbide (UC) site and the North Continent (NC) site, and for the proposed Burro Canyon disposal site. The water resources protection strategy that describes how the proposed action will comply with the EPA ground water protection standards is presented in Attachment 4. The following site characterization activities are discussed in this attachment: Characterization of the hydrogeologic environment, including hydrostratigraphy, ground water occurrence, aquifer parameters, and areas of recharge and discharge. Characterization of existing ground water quality by comparison with background water quality and the maximum concentration limits (MCL) of the proposed EPA ground water protection standards. Definition of physical and chemical characteristics of the potential contaminant source, including concentration and leachability of the source in relation to migration in ground water and hydraulically connected surface water. Description of local water resources, including current and future use, availability, and alternative supplies.

  20. Remedial Action Plan and Site Design for Stabilization of the Inactive Uranium Mill Tailings Site, Maybell, Colorado. Remedial action selection report: Attachment 2, Geology report, Final

    SciTech Connect

    Not Available

    1994-06-01

    The Maybell uranium mill tailings site is 25 miles (mi) (40 kilometers [km]) west of the town of Craig, Colorado, in Moffat County, in the northwestern part of the state. The unincorporated town of Maybell is 5 road mi (8 km) southwest of the site. The designated site covers approximately 110 acres (ac) (45 hectares [ha]) and consists of a concave-shaped tailings pile and rubble from the demolition of the mill buildings buried in the former mill area. Contaminated materials at the Maybell processing site include the tailings pile, which has an average depth of 20 feet (ft) (6 meters [m]) and contains 2.8 million cubic yards (yd{sup 3}) (2.1 million cubic meters [m{sup 3}]) of tailings. The former mill processing area is on the north side of the site and contains 20,000 yd{sup 3} (15,000 m{sup 3}) of contaminated demolition debris. Off-pile contamination is present and includes areas adjacent to the tailings pile, as well as contamination dispersed by wind and surface water flow. The volume of off-pile contamination to be placed in the disposal cell is 550,000 yd{sup 3} (420,000 m{sup 3}). The total volume of contaminated materials to be disposed of as part of the remedial action is estimated to be 3.37 million yd{sup 3} (2.58 million m{sup 3}). Information presented in this Final Remedial Action Plan (RAP) and referenced in supporting documents represents the current disposal cell design features and ground water compliance strategy proposed by the US Department of Energy (DOE) for the Maybell, Colorado, tailings site. Both the disposal cell design and the ground water compliance strategy have changed from those proposed prior to the preliminary final RAP document as a result of prudent site-specific technical evaluations.

  1. Identification of Ice Nucleation Active Sites on Feldspar Dust Particles

    PubMed Central

    2015-01-01

    Mineral dusts originating from Earth’s crust are known to be important atmospheric ice nuclei. In agreement with earlier studies, feldspar was found as the most active of the tested natural mineral dusts. Here we investigated in closer detail the reasons for its activity and the difference in the activity of the different feldspars. Conclusions are drawn from scanning electron microscopy, X-ray powder diffraction, infrared spectroscopy, and oil-immersion freezing experiments. K-feldspar showed by far the highest ice nucleation activity. Finally, we give a potential explanation of this effect, finding alkali-metal ions having different hydration shells and thus an influence on the ice nucleation activity of feldspar surfaces. PMID:25584435

  2. Site investigation of Cluster 3, Edgewood Area, Aberdeen Proving Ground, Maryland. Final report

    SciTech Connect

    Sharp, M.K.; Kean, T.B.

    1995-08-01

    The Waterways Experiment Station (WES) is currently involved in investigating several sites at the Edgewood Area (EA) of Aberdeen Proving Ground (APG), Maryland. These investigations consist of placing monitoring wells and periodically collecting samples for laboratory analysis. Additionally, several of the sites are to be investigated geophysically to determine if any anomalous areas exist. One of the sites, Cluster 3, a suspected landfill area is the focus of this report. Geophysical surveys were conducted to help delineate any anomalies indicative of buried waste, waste containers, boundaries of burial trenches, and the depth to water table. The geophysical methods utilized at the site were electromagnetic induction (EM), magnetics, and seismic refraction.

  3. Kv3 channel assembly, trafficking and activity are regulated by zinc through different binding sites.

    PubMed

    Gu, Yuanzheng; Barry, Joshua; Gu, Chen

    2013-05-15

    Zinc, a divalent heavy metal ion and an essential mineral for life, regulates synaptic transmission and neuronal excitability via ion channels. However, its binding sites and regulatory mechanisms are poorly understood. Here, we report that Kv3 channel assembly, localization and activity are regulated by zinc through different binding sites. Local perfusion of zinc reversibly reduced spiking frequency of cultured neurons most likely by suppressing Kv3 channels. Indeed, zinc inhibited Kv3.1 channel activity and slowed activation kinetics, independent of its site in the N-terminal T1 domain. Biochemical assays surprisingly identified a novel zinc-binding site in the Kv3.1 C-terminus, critical for channel activity and axonal targeting, but not for the zinc inhibition. Finally, mutagenesis revealed an important role of the junction between the first transmembrane (TM) segment and the first extracellular loop in sensing zinc. Its mutant enabled fast spiking with relative resistance to the zinc inhibition. Therefore, our studies provide novel mechanistic insights into the multifaceted regulation of Kv3 channel activity and localization by divalent heavy metal ions.

  4. Final environmental impact statement for the Nevada Test Site and off-site locations in the state of Nevada: Mitigation action plan

    SciTech Connect

    1997-02-01

    The DOE Notice of Availability for this environmental impact statement was published in the Federal Register on Friday, October 18, 1996 (61 FR 54437). The final environmental impact statement identifies potential adverse effects resulting from the four use alternatives evaluated and discusses measures that DOE considered for the mitigation of these potential adverse effects. The Secretary of Energy signed the Record of Decision on the management and operation of the Nevada Test Site and other DOE sites in the state of Nevada on December 9, 1996. These decisions will result in the continuation of the multipurpose, multi-program use of the Nevada Test Site, under which DOE will pursue a further diversification of interagency, private industry, and public-education uses while meeting its Defense Program, Waste Management, and Environmental Restoration mission requirements at the Nevada Test Site and other Nevada sites, including the Tonopah Test Range, the Project Shoal Site, the Central Nevada Test Area, and on the Nellis Air Force Range Complex. The Record of Decision also identifies specific mitigation actions beyond the routine day-to-day physical and administrative controls needed for implementation of the decisions. These specific mitigation actions are focused on the transportation of waste and on groundwater availability. This Mitigation Action Plan elaborates on these mitigation commitments.

  5. Identification of Ice Nucleation Active Sites on Silicate Dust Particles

    NASA Astrophysics Data System (ADS)

    Zolles, Tobias; Burkart, Julia; Häusler, Thomas; Pummer, Bernhard; Hitzenberger, Regina; Grothe, Hinrich

    2015-04-01

    Mineral dusts originating from Earth's crust are known to be important atmospheric ice nuclei. In agreement with earlier studies, feldspar was found as the most active of the tested natural mineral dusts [1-3]. Nevertheless, among those structures K-feldspar showed by far the highest ice nucleation activity. In this study, the reasons for its activity and the difference in the activity of the different feldspars were investigated in closer details. Conclusions are drawn from scanning electron microscopy, X-ray powder diffraction, infrared spectroscopy, and oil-immersion freezing experiments. We give a potential explanation of the increased ice nucleation activity of K-feldspar. The ice nucleating sites are very much dependent on the alkali ion present by altering the water structure and the feldspar surface. The higher activity of K-feldspar can be attributed to the presence of potassium ions on the surface and surface bilayer. The alkali-ions have different hydration shells and thus an influence on the ice nucleation activity of feldspar. Chaotropic behavior of Calcium and Sodium ions are lowering the ice nucleation potential of the other feldspars, while kosmotropic Potassium has a neutral or even positive effect. Furthermore we investigated the influence of milling onto the ice nucleation of quartz particles. The ice nucleation activity can be increased by mechanical milling, by introducing more molecular, nucleation active defects to the particle surface. This effect is larger than expected by plane surface increase. [1] Atkinson et al. The Importance of Feldspar for Ice Nucleation by Mineral Dust in Mixed-Phase Clouds. Nature 2013, 498, 355-358. [2] Yakobi-Hancock et al.. Feldspar Minerals as Efficient Deposition Ice Nuclei. Atmos. Chem. Phys. 2013, 13, 11175-11185. [3] Zolles et al. Identification of Ice Nucleation Active Sites on Feldspar Dust Particles. J. Phys. Chem. A 2015 accepted.

  6. Face the Edges: Catalytic Active Sites of Nanomaterials

    PubMed Central

    Ni, Bing

    2015-01-01

    Edges are special sites in nanomaterials. The atoms residing on the edges have different environments compared to those in other parts of a nanomaterial and, therefore, they may have different properties. Here, recent progress in nanomaterial fields is summarized from the viewpoint of the edges. Typically, edge sites in MoS2 or metals, other than surface atoms, can perform as active centers for catalytic reactions, so the method to enhance performance lies in the optimization of the edge structures. The edges of multicomponent interfaces present even more possibilities to enhance the activities of nanomaterials. Nanoframes and ultrathin nanowires have similarities to conventional edges of nanoparticles, the application of which as catalysts can help to reduce the use of costly materials. Looking beyond this, the edge structures of graphene are also essential for their properties. In short, the edge structure can influence many properties of materials. PMID:27980960

  7. A Variable Active Site Residue Influences the Kinetics of Response Regulator Phosphorylation and Dephosphorylation.

    PubMed

    Immormino, Robert M; Silversmith, Ruth E; Bourret, Robert B

    2016-10-04

    Two-component regulatory systems, minimally composed of a sensor kinase and a response regulator protein, are common mediators of signal transduction in microorganisms. All response regulators contain a receiver domain with conserved active site residues that catalyze the signal activating and deactivating phosphorylation and dephosphorylation reactions. We explored the impact of variable active site position T+1 (one residue C-terminal to the conserved Thr/Ser) on reaction kinetics and signaling fidelity, using wild type and mutant Escherichia coli CheY, CheB, and NarL to represent the three major sequence classes observed across response regulators: Ala/Gly, Ser/Thr, and Val/Ile/Met, respectively, at T+1. Biochemical and structural data together suggested that different amino acids at T+1 impacted reaction kinetics by altering access to the active site while not perturbing overall protein structure. A given amino acid at position T+1 had similar effects on autodephosphorylation in each protein background tested, likely by modulating access of the attacking water molecule to the active site. Similarly, rate constants for CheY autophosphorylation with three different small molecule phosphodonors were consistent with the steric constraints on access to the phosphorylation site arising from combination of specific phosphodonors with particular amino acids at T+1. Because other variable active site residues also influence response regulator phosphorylation biochemistry, we began to explore how context (here, the amino acid at T+2) affected the influence of position T+1 on CheY autocatalytic reactions. Finally, position T+1 affected the fidelity and kinetics of phosphotransfer between sensor kinases and response regulators but was not a primary determinant of their interaction.

  8. Technical report of biota, FEL Site 1, Lawrence Livermore National Laboratory: Final report

    SciTech Connect

    Taylor, D.W.; Davilla, W.; Orloff, S.

    1986-09-26

    Lawrence Livermore National Laboratory is considering an expansion of laser test facilities adjacent to its existing LLNL Site 300 test location. Construction of a free-electron laser, known as the FEL Project, is being considered on approximately 3900 hectates (10,500 acres) of land. We will refer to this proposed site as FEL Site 1. Knowledge of the flora and vegetation resources of the proposed FEL Site 1 is necessary in order to plan for construction, operation, and possible future expansion of the FEL facility. The purpose of botanical sections of this report is to quantitatively describe the variation of vegetation on FEL Site 1, and to relate the vegetation to potential environmental impacts associated with present operation and possible expansion of site facilities. The primary purpose of the wildlife studies was to determine the presence and status of any endangered, threatened, fully protected, or otherwise sensitive species on FEL Site 1 that might be affected by the proposed FEL project. We directed our studies mainly toward the federally endangered San Joaquin kit fox (Vulpes macrotis mutica), but also toward another 14 special status species that potentially occur on site, including the state threatened Alameda striped racer (Masticophis lateralis euryxanthus).

  9. SUPERFUND TREATABILITY CLEARINGHOUSE: FINAL REPORT, PHASE I - IMMEDIATE ASSESSMENT, ACME SOLVENTS SITE

    EPA Science Inventory

    This is a site assessment and feasibility study of incineration alternatives at the ACME Solvents Site at Rockford, Illinois. The document contains laboratory results that are reported to simulate incineration conditions but no details on test methods were provided. The d...

  10. Comprehensive Illinois Occupational Education. Demonstration Center. Site B. Kindergarten-Grade 14. Final Report.

    ERIC Educational Resources Information Center

    Lake Land Coll., Mattoon, IL.

    The CIOEDC (Comprehensive Illinois Occupational Education Demonstration Center) project, Site B, in Toledo, Illinois (from February 15, 1976 to June 30, 1976) was conducted in three phases--planning, implementation, and demonstration. Specific objectives for this site were to (1) supplement present programs of career awareness and exploration…

  11. Environmental assessment of remedial action at the Lowman Uranium Mill Tailings Site near Lowman, Idaho. Final

    SciTech Connect

    Not Available

    1991-01-01

    This document assesses the environmental impacts of stabilization on site of the contaminated materials at the Lowman uranium mill tailings site. The Lowman site is 0.5 road mile northeast of the unincorporated village of Lowman, Idaho, and 73 road miles from Boise, Idaho. The Lowman site consists of piles of radioactive sands, an ore storage area, abandoned mill buildings, and windblown/waterborne contaminated areas. A total of 29.5 acres of land are contaminated and most of this land occurs within the 35-acre designated site boundary. The proposed action is to stabilize the tailings and other contaminated materials on the site. A radon barrier would be constructed over the consolidated residual radioactive materials and various erosion control measures would be implemented to ensure the long-term stability of the disposal cell. Radioactive constituents and other hazardous constituents were not detected in the groundwater beneath the Lowman site. The groundwater beneath the disposal cell would not become contaminated during or after remedial action so the maximum concentration limits or background concentrations for the contaminants listed in the draft EPA groundwater protection standards would be met at the point of compliance. No significant impacts were identified as a result of the proposed remedial action at the Lowman site.

  12. PISCES field chemical emissions monitoring project: Site 20 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power Plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 20. Site 20 is a pulverized coal-fired boiler burning a medium-sulfur bituminous coal. Site 20 is a large, pulverized coal-fired power plant that bums a lignite coal. Site 20 employs electrostatic precipitators and a flue gas desulfurization system for particulate and SO{sub 2} control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts-as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites.

  13. Nest predation increases with parental activity: Separating nest site and parental activity effects

    USGS Publications Warehouse

    Martin, T.E.; Scott, J.; Menge, C.

    2000-01-01

    Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators have found similar results. We tested whether nest site effects might yield higher predation during incubation because the most obvious sites are depredated most rapidly. We conducted experiments using nest sites from the previous year to remove parental activity. Our results showed that nest sites have highly repeatable effects on nest predation risk; poor nest sites incurred rapid predation and caused predation rates to be greater during the incubation than nestling stage. This pattern also was exhibited in a bird species with similar (i.e. controlled) parental activity between nesting stages. Once nest site effects are taken into account, nest predation shows a strong proximate increase with parental activity during the nestling stage within and across species. Parental activity and nest sites exert antagonistic influences on current estimates of nest predation between nesting stages and both must be considered in order to understand current patterns of nest predation, which is an important source of natural selection.

  14. Nest predation increases with parental activity: separating nest site and parental activity effects.

    PubMed Central

    Martin, T E; Scott, J; Menge, C

    2000-01-01

    Alexander Skutch hypothesized that increased parental activity can increase the risk of nest predation. We tested this hypothesis using ten open-nesting bird species in Arizona, USA. Parental activity was greater during the nestling than incubation stage because parents visited the nest frequently to feed their young during the nestling stage. However, nest predation did not generally increase with parental activity between nesting stages across the ten study species. Previous investigators have found similar results. We tested whether nest site effects might yield higher predation during incubation because the most obvious sites are depredated most rapidly. We conducted experiments using nest sites from the previous year to remove parental activity. Our results showed that nest sites have highly repeatable effects on nest predation risk; poor nest sites incurred rapid predation and caused predation rates to be greater during the incubation than nestling stage. This pattern also was exhibited in a bird species with similar (i.e. controlled) parental activity between nesting stages. Once nest site effects are taken into account, nest predation shows a strong proximate increase with parental activity during the nestling stage within and across species. Parental activity and nest sites exert antagonistic influences on current estimates of nest predation between nesting stages and both must be considered in order to understand current patterns of nest predation, which is an important source of natural selection. PMID:11413645

  15. Active site amino acid sequence of human factor D.

    PubMed

    Davis, A E

    1980-08-01

    Factor D was isolated from human plasma by chromatography on CM-Sephadex C50, Sephadex G-75, and hydroxylapatite. Digestion of reduced, S-carboxymethylated factor D with cyanogen bromide resulted in three peptides which were isolated by chromatography on Sephadex G-75 (superfine) equilibrated in 20% formic acid. NH2-Terminal sequences were determined by automated Edman degradation with a Beckman 890C sequencer using a 0.1 M Quadrol program. The smallest peptide (CNBr III) consisted of the NH2-terminal 14 amino acids. The other two peptides had molecular weights of 17,000 (CNBr I) and 7000 (CNBr II). Overlap of the NH2-terminal sequence of factor D with the NH2-terminal sequence of CNBr I established the order of the peptides. The NH2-terminal 53 residues of factor D are somewhat more homologous with the group-specific protease of rat intestine than with other serine proteases. The NH2-terminal sequence of CNBr II revealed the active site serine of factor D. The typical serine protease active site sequence (Gly-Asp-Ser-Gly-Gly-Pro was found at residues 12-17. The region surrounding the active site serine does not appear to be more highly homologous with any one of the other serine proteases. The structural data obtained point out the similarities between factor D and the other proteases. However, complete definition of the degree of relationship between factor D and other proteases will require determination of the remainder of the primary structure.

  16. [Mechanism of arginine deiminase activity by site-directed mutagenesis].

    PubMed

    Li, Lifeng; Ni, Ye; Sun, Zhihao

    2012-04-01

    Arginine deiminase (ADI) has been studied as a potential anti-cancer agent for inhibiting arginine-auxotrophic tumors (such as melanomas and hepatocellular carcinomas) in phase III clinical trials. In this work, we studied the molecular mechanism of arginine deiminase activity by site-directed mutagenesis. Three mutation sites, A128, H404 and 1410, were introduced into wild-type ADI gene by QuikChange site-directed mutagenesis method, and four ADI mutants M1 (A128T), M2 (H404R), M3 (I410L), and M4 (A128T, H404R) were obtained. The ADI mutants were individually expressed in Escherichia coli BL21 (DE3), and the enzymatic properties of the purified mutant proteins were determined. The results show that both A128T and H404R had enhanced optimum pH, higher activity and stability of ADI under physiological condition (pH 7.4), as well as reduced K(m) value. This study provides an insight into the molecular mechanism of the ADI activity, and also the experimental evidence for the rational protein evolution in the future.

  17. Potential sites of CFTR activation by tyrosine kinases

    PubMed Central

    Billet, Arnaud; Jia, Yanlin; Jensen, Timothy J.; Hou, Yue-Xian; Chang, Xiu-Bao; Riordan, John R.; Hanrahan, John W.

    2016-01-01

    ABSTRACT The CFTR chloride channel is tightly regulated by phosphorylation at multiple serine residues. Recently it has been proposed that its activity is also regulated by tyrosine kinases, however the tyrosine phosphorylation sites remain to be identified. In this study we examined 2 candidate tyrosine residues near the boundary between the first nucleotide binding domain and the R domain, a region which is important for channel function but devoid of PKA consensus sequences. Mutating tyrosines at positions 625 and 627 dramatically reduced responses to Src or Pyk2 without altering the activation by PKA, suggesting they may contribute to CFTR regulation. PMID:26645934

  18. MSK1 activity is controlled by multiple phosphorylation sites

    PubMed Central

    McCOY, Claire E.; Campbell, David G.; Deak, Maria; Bloomberg, Graham B.; Arthur, J. Simon C.

    2004-01-01

    MSK1 (mitogen- and stress-activated protein kinase) is a kinase activated in cells downstream of both the ERK1/2 (extracellular-signal-regulated kinase) and p38 MAPK (mitogen-activated protein kinase) cascades. In the present study, we show that, in addition to being phosphorylated on Thr-581 and Ser-360 by ERK1/2 or p38, MSK1 can autophosphorylate on at least six sites: Ser-212, Ser-376, Ser-381, Ser-750, Ser-752 and Ser-758. Of these sites, the N-terminal T-loop residue Ser-212 and the ‘hydrophobic motif’ Ser-376 are phosphorylated by the C-terminal kinase domain of MSK1, and their phosphorylation is essential for the catalytic activity of the N-terminal kinase domain of MSK1 and therefore for the phosphorylation of MSK1 substrates in vitro. Ser-381 is also phosphorylated by the C-terminal kinase domain, and mutation of Ser-381 decreases MSK1 activity, probably through the inhibition of Ser-376 phosphorylation. Ser-750, Ser-752 and Ser-758 are phosphorylated by the N-terminal kinase domain; however, their function is not known. The activation of MSK1 in cells therefore requires the activation of the ERK1/2 or p38 MAPK cascades and does not appear to require additional signalling inputs. This is in contrast with the closely related RSK (p90 ribosomal S6 kinase) proteins, whose activity requires phosphorylation by PDK1 (3-phosphoinositide-dependent protein kinase 1) in addition to phosphorylation by ERK1/2. PMID:15568999

  19. Novel active comb-shaped dry electrode for EEG measurement in hairy site.

    PubMed

    Huang, Yan-Jun; Wu, Chung-Yu; Wong, Alice May-Kuen; Lin, Bor-Shyh

    2015-01-01

    Electroencephalography (EEG) is an important biopotential, and has been widely applied in clinical applications. The conventional EEG electrode with conductive gels is usually used for measuring EEG. However, the use of conductive gel also encounters with the issue of drying and hardening. Recently, many dry EEG electrodes based on different conductive materials and techniques were proposed to solve the previous issue. However, measuring EEG in the hairy site is still a difficult challenge. In this study, a novel active comb-shaped dry electrode was proposed to measure EEG in hairy site. Different form other comb-shaped or spike-shaped dry electrodes, it can provide more excellent performance of avoiding the signal attenuation, phase distortion, and the reduction of common mode rejection ratio. Even under walking motion, it can effectively acquire EEG in hairy site. Finally, the experiments for alpha rhythm and steady-state visually evoked potential were also tested to validate the proposed electrode.

  20. Final record of decision/remedial action plan, nine sites, Sierra Army Depot, Lassen County, California

    SciTech Connect

    Arroyo, S.L.; Larson, A.M.; Parent, M.M.; Silvers, J.M.; Weaverling, P.H.

    1996-10-01

    This ROD/RAP presents the selected response actions for nine sites at SIAD. The response actions were selected by the US Department of the Army (Army) in accordance with the Comprehensive Environmental Response, Compensation, and Liability Act (CERCLA), as amended by the Superfund Amendments Reauthorization Act of 1986 (SARA)(collectively referred to as CERCLA), the National Oil and Hazardous Substances Pollution Contingency Plan (NCP), and Section 6.8 of the California Health and Safety Code. This ROD/RAP includes the factual and legal basis for selecting the response action at each of the nine sites listed above. The data used to support the selected response action are contained in the Administrative Record for each site. The State of California as represented by the Department of Toxic Substances Control (DTSC), and the Lahontan Regional Water Quality Control Board (RWQCB) concur with the selected response action at each site.

  1. Final Report: Independent Design Review, Celanese Fiber Operations Superfund Site, Shelby, North Carolina, EPA Region 4

    EPA Pesticide Factsheets

    The Celanese site is located in Shelby, North Carolina. Operation of the P&T system was discontinued on a trial basis for two years to evaluate monitored natural attenuation as a potential ground water remedy.

  2. PISCES field chemical emissions monitoring project: Site 19 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 19. Site 19 is a pulverized coal-fired boiler burning a medium-sulfur bituminous coal. Site 19 employs electrostatic precipitators for particulate control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  3. PISCES field chemical emissions monitoring project: Site 102 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 102. Site 102 is a cyclone boiler burning a sub-bituminous coal. Site 102 employs an electrostatic precipitator for particulate control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  4. PISCES field chemical emissions monitoring project: Site 101 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 101. Site 101 is a pulverized coal-fired boiler burning a sub-bituminous coal. Site 101 employs a reverse-gas fabric filter for particulate control and a wet limestone flue gas desulfurization system for SO{sub 2} control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts-as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites.

  5. PISCES Field Chemical Emissions Monitoring project: Site 15 emissions report. Final report

    SciTech Connect

    1995-11-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 15. Site 15 is a pulverized coal-fired boiler burning a medium-sulfur bituminous coal. Site 15 employs electrostatic precipitators for particulate control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  6. PISCES field chemical emissions monitoring project: Site 22 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 22. Site 22 is a large, pulverized coal-fired boiler burning a low-sulfur sub-bituminous coal. Site 22 employs electrostatic precipitators for particulate control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts-as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites.

  7. PISCES field chemical emissions monitoring project: Site 16 emissions report. Final report

    SciTech Connect

    1995-11-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 16. Site 16 is a pulverized coal-fired boiler burning a medium-sulfur bituminous coal. Site 16 employs electrostatic precipitators for particulate control. Measurements were conducted under two modifications: overfire air and a combination of overfire air with low-NO{sub x} burners. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts -- as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites.

  8. An economic analysis of a monitored retrievable storage site for Tennessee. Final report and appendices

    SciTech Connect

    Fox, W.F.; Mayo, J.W.; Hansen, L.T.; Quindry, K.E.

    1985-12-17

    The United States Department of Energy is charged with the task of identifying potential sites for a Monitored Retrievable Storage (MRS) Facility and reporting the results of its analysis to Congress by January 1986. DOE chose three finalist sites from 11 sites DOE analysts evaluated earlier. All three are in Tennessee, including two in Oak Ridge and one in Trousdale/Smith Counties. This paper is a summary of research undertaken on the economic effects of establishing the MRS facility in Tennessee. All three locations were considered in the analysis, but on some occasions attention is focused on the site preferred by DOE. The research was undertaken by the Center for Business and Economic Research (CBER), College of Business Administration, the University of Tennessee, Knoxville, under contract with the Tennessee Department of Economic and Community Development.

  9. Environmental assessment of remedial action at the Gunnison Uranium Mill Tailings Site near Gunnison, Colorado. Final

    SciTech Connect

    Not Available

    1992-02-01

    The presence of contaminated uranium mill tailings adjacent to the city of Gunnison has been a local concern for many years. The following issues were identified during public meetings that were held by the DOE prior to distribution of an earlier version of this EA. Many of these issues will require mitigation. Groundwater contamination; in December 1989, a herd of 105 antelope were introduced in an area that includes the Landfill disposal site. There is concern that remedial action-related traffic in the area would result in antelope mortality. The proposed Tenderfoot Mountain haul road may restrict antelope access to their water supply; a second wildlife issue concerns the potential reduction in sage grouse use of breeding grounds (leks) and nesting habitat; the proposed Tenderfoot Mountain haul road would cross areas designated as wetlands by US Army Corps of Engineers (COE); the proposed disposal site is currently used for grazing by cattle six weeks a year in the spring. Additional concerns were stated in comments on a previous version of this EA. The proposed action is to consolidate and remove all contaminated materials associated with the Gunnison processing site to the Landfill disposal site six air miles east of Gunnison. All structures on the site (e.g., water tower, office buildings) were demolished in 1991. The debris is being stored on the site until it can be incorporated into the disposal cell at the disposal site. All contaminated materials would be trucked to the Landfill disposal site on a to-be-constructed haul road that crosses BLM-administered land.

  10. Final Phase I-Phase II interim report : expedited site characterization, Morrill, Kansas.

    SciTech Connect

    LaFreniere, L. M.

    2005-10-20

    The city of Morrill, Kansas, is located in Brown County, in the northeastern corner of the state. The town lies about 7 mi east of Sabetha and about 10 mi northwest of Hiawatha (Figure 1.1). The population of Morrill as of the 2000 census was approximately 277. The Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA), operated a grain storage facility in the northwestern section of Morrill from 1950 until 1971. The property continued to be used for grain storage after 1971. Fourteen of the original 21 CCC/USDA circular bin structures remain today. Prior to 1986, commercial grain fumigants containing carbon tetrachloride were commonly used by the CCC/USDA and the grain storage industry to preserve grain. Contamination with carbon tetrachloride, also known as tetrachloromethane, was initially identified in groundwater at Morrill in October 1985 in public water supply well PWS5, during statewide testing of public water supply wells for volatile organic compounds (VOCs). A preliminary assessment was completed by the Kansas Department of Health and Environment (KDHE) in 1989 to obtain background information on the Morrill public water supply and to identify potential sources of the detected carbon tetrachloride contamination (KDHE 1989). Since 1991 the city of Morrill has obtained its water by pipeline from the municipal water supply of Sabetha. Water supplied through the Sabetha system comes from a surface reservoir. Former public wells in Morrill are no longer used for municipal supply. Wells PWS3, PWS4, and PWS5 were plugged in 1993. Wells PWS1 and PWS2 are no longer in active production, but they continue to be available for non-drinking purposes such as bulk hauling for agricultural uses, fire fighting, and road work (Hansen 2001). Because the KDHE found carbon tetrachloride in the groundwater at the former CCC/USDA facility at Morrill that could, in part, be linked to historical use of carbon tetrachloride-based grain

  11. PISCES Field Chemical Emissions Monitoring project: Site 10 emissions report. Final report

    SciTech Connect

    1995-11-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions at Site 10. Site 10 is a fluidized bed combustor that burns a low-sulfur sub-bituminous coal. Site l0 is a fluidized bed combustor that burns a low-sulfur sub-bituminous coal. Site 10 employs a fabric filter for particulate control. Limestone is fed into the fluidized bed for SO{sub 2} control. Testing at Site 10 was performed in the summer of 1990, with addition retests conducted for volatile organic compounds (VOCs). The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  12. Sperry Low Temperature Geothermal Conversion System, Phase I and Phase II. Volume IV. Field activities. Final report

    SciTech Connect

    Harvey, C.

    1984-01-01

    This volume describes those activities which took place at the Sperry DOE Gravity Head plant site at the East Mesa Geothermal Reservoir near Holtville, California between February 1980, when site preparation was begun, and November 1982, when production well 87-6 was permanently abandoned. Construction activities were terminated in July 1981 following the liner collapse in well 87-6. Large amounts of program time manpower, materials, and funds had been diverted in a nine-month struggle to salvage the production well. Once these efforts proved futile, there was no rationale for continuing with the site work unless and until sufficient funding to duplicate well 87-6 was obtained. Activities reported here include: plant construction and pre-operational calibration and testing, drilling and completion of well 87-6, final repair effort on well 87-6, abandonment of well 87-6, and performance evaluation of well 87.6. (MHR)

  13. Modification No. 2 to the remedial action plan and site design for stabilization of the inactive uranium mill tailings site at Green River, Utah: Final

    SciTech Connect

    1996-11-01

    Portions of the final Remedial Action Plan (RAP) for the Green River site, Volumes 1 and 2, Appendix B of the Cooperative Agreement No. DE-FC04-81AL16257, March 1991 (DOE, 1991) have been modified. The changes to the RAP are designated as RAP Modification No. 2. These changes have been placed in a three-ring binder that will supplement the original RAP (DOE, 1991), and include the following: addendum to the Executive Summary; Section 3.5 (Ground Water part of the Site Characterization Summary); Section 4.0 (Site Design); Section5.0 (Water Resources Protection Strategy Summary); Appendix D.5 (Ground Water Hydrology); and Appendix E (Ground Water Protection Strategy). In addition to these revisions, there have been editorial changes that clarify the text, but do not change the meaning. Also, certain sections of the document, which are included in the submittal for ease of review and continuity, have been updated to reflect the final ground water protection standards and the current UMTRA Project format and content of RAPs.

  14. New active site oriented glyoxyl-agarose derivatives of Escherichia coli penicillin G acylase

    PubMed Central

    Cecchini, Davide A; Serra, Immacolata; Ubiali, Daniela; Terreni, Marco; Albertini, Alessandra M

    2007-01-01

    Background Immobilized Penicillin G Acylase (PGA) derivatives are biocatalysts that are industrially used for the hydrolysis of Penicillin G by fermentation and for the kinetically controlled synthesis of semi-synthetic β-lactam antibiotics. One of the most used supports for immobilization is glyoxyl-activated agarose, which binds the protein by reacting through its superficial Lys residues. Since in E. coli PGA Lys are also present near the active site, an immobilization that occurs through these residues may negatively affect the performance of the biocatalyst due to the difficult diffusion of the substrate into the active site. A preferential orientation of the enzyme with the active site far from the support surface would be desirable to avoid this problem. Results Here we report how it is possible to induce a preferential orientation of the protein during the binding process on aldehyde activated supports. A superficial region of PGA, which is located on the opposite side of the active site, is enriched in its Lys content. The binding of the enzyme onto the support is consequently forced through the Lys rich region, thus leaving the active site fully accessible to the substrate. Different mutants with an increasing number of Lys have been designed and, when active, immobilized onto glyoxyl agarose. The synthetic performances of these new catalysts were compared with those of the immobilized wild-type (wt) PGA. Our results show that, while the synthetic performance of the wt PGA sensitively decreases after immobilization, the Lys enriched mutants have similar performances to the free enzyme even after immobilization. We also report the observations made with other mutants which were unable to undergo a successful maturation process for the production of active enzymes or which resulted toxic for the host cell. Conclusion The desired orientation of immobilized PGA with the active site freely accessible can be obtained by increasing the density of Lys residues

  15. Current activities handbook: formerly utilized sites remedial action program

    SciTech Connect

    1981-02-27

    This volume is one of a series produced under contract with the DOE, by Politech Corporation to develop a legislative and regulatory data base to assist the FUSRAP management in addressing the institutional and socioeconomic issues involved in carrying out the Formerly Utilized Sites Remedial Action Program. This Information Handbook series contains information about all relevant government agencies at the Federal and state levels, the pertinent programs they administer, each affected state legislature, and current Federal and state legislative and regulatory initiatives. This volume is a compilation of information about the activities each of the thirteen state legislatures potentially affected by the Formerly Utilized Sites Remedial Action Program. It contains a description of the state legislative procedural rules and a schedule of each legislative session; a summary of pending relevant legislation; the name and telephone number of legislative and state agency contacts; and the full text of all bills identified.

  16. Vitamin K epoxide reductase: homology, active site and catalytic mechanism.

    PubMed

    Goodstadt, Leo; Ponting, Chris P

    2004-06-01

    Vitamin K epoxide reductase (VKOR) recycles reduced vitamin K, which is used subsequently as a co-factor in the gamma-carboxylation of glutamic acid residues in blood coagulation enzymes. VKORC1, a subunit of the VKOR complex, has recently been shown to possess this activity. Here, we show that VKORC1 is a member of a large family of predicted enzymes that are present in vertebrates, Drosophila, plants, bacteria and archaea. Four cysteine residues and one residue, which is either serine or threonine, are identified as likely active-site residues. In some plant and bacterial homologues the VKORC1 homologous domain is fused with domains of the thioredoxin family of oxidoreductases. These might reduce disulfide bonds of VKORC1-like enzymes as a prerequisite for their catalytic activities.

  17. Fibromodulin Interacts with Collagen Cross-linking Sites and Activates Lysyl Oxidase*

    PubMed Central

    Bihan, Dominique; Bonna, Arkadiusz; Rubin, Kristofer; Farndale, Richard W.

    2016-01-01

    The hallmark of fibrotic disorders is a highly cross-linked and dense collagen matrix, a property driven by the oxidative action of lysyl oxidase. Other fibrosis-associated proteins also contribute to the final collagen matrix properties, one of which is fibromodulin. Its interactions with collagen affect collagen cross-linking, packing, and fibril diameter. We investigated the possibility that a specific relationship exists between fibromodulin and lysyl oxidase, potentially imparting a specific collagen matrix phenotype. We mapped the fibromodulin-collagen interaction sites using the collagen II and III Toolkit peptide libraries. Fibromodulin interacted with the peptides containing the known collagen cross-linking sites and the MMP-1 cleavage site in collagens I and II. Interestingly, the interaction sites are closely aligned within the quarter-staggered collagen fibril, suggesting a multivalent interaction between fibromodulin and several collagen helices. Furthermore, we detected an interaction between fibromodulin and lysyl oxidase (a major collagen cross-linking enzyme) and mapped the interaction site to 12 N-terminal amino acids on fibromodulin. This interaction also increases the activity of lysyl oxidase. Together, the data suggest a fibromodulin-modulated collagen cross-linking mechanism where fibromodulin binds to a specific part of the collagen domain and also forms a complex with lysyl oxidase, targeting the enzyme toward specific cross-linking sites. PMID:26893379

  18. Fibromodulin Interacts with Collagen Cross-linking Sites and Activates Lysyl Oxidase.

    PubMed

    Kalamajski, Sebastian; Bihan, Dominique; Bonna, Arkadiusz; Rubin, Kristofer; Farndale, Richard W

    2016-04-08

    The hallmark of fibrotic disorders is a highly cross-linked and dense collagen matrix, a property driven by the oxidative action of lysyl oxidase. Other fibrosis-associated proteins also contribute to the final collagen matrix properties, one of which is fibromodulin. Its interactions with collagen affect collagen cross-linking, packing, and fibril diameter. We investigated the possibility that a specific relationship exists between fibromodulin and lysyl oxidase, potentially imparting a specific collagen matrix phenotype. We mapped the fibromodulin-collagen interaction sites using the collagen II and III Toolkit peptide libraries. Fibromodulin interacted with the peptides containing the known collagen cross-linking sites and the MMP-1 cleavage site in collagens I and II. Interestingly, the interaction sites are closely aligned within the quarter-staggered collagen fibril, suggesting a multivalent interaction between fibromodulin and several collagen helices. Furthermore, we detected an interaction between fibromodulin and lysyl oxidase (a major collagen cross-linking enzyme) and mapped the interaction site to 12 N-terminal amino acids on fibromodulin. This interaction also increases the activity of lysyl oxidase. Together, the data suggest a fibromodulin-modulated collagen cross-linking mechanism where fibromodulin binds to a specific part of the collagen domain and also forms a complex with lysyl oxidase, targeting the enzyme toward specific cross-linking sites.

  19. PISCES field chemical emissions monitoring project: Site 12 emissions report. Final report

    SciTech Connect

    1995-10-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 12. Site 12 is a large, pulverized coal-fired power plant that burns a medium-sulfur bituminous coal. Site 12 employs electrostatic precipitators and a flue gas desulfurization system for particulate and S02 control. Testing at Site 12 was performed in the summer of 1990, with additional retests in August and December of 1992 for volatile organic compounds (VOCs) and mercury, respectively. Sampling and analytical problems during the initial test period necessitated the retests. The objective of this report is to transmit the detailed data to the U.S. Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts-as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  20. PISCES field chemical emissions monitoring project: Site 11 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 11. Site 11 is a large, pulverized coal-fired power plant that burns a low-sulfur sub-bituminous coal. Site 11 employs electrostatic precipitators and a flue gas desulfurization system for particulate and SO{sub 2} control. Testing at Site 11 was performed in the summer of 1990, with additional retests in August 1992 and April 1993 for volatile organic compounds (VOCs) and mercury, respectively. Sampling and analytical problems during the initial test period necessitated the retests. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  1. Evaluation of the likelihood of DNAPL presence at NPL sites: National results. Final report

    SciTech Connect

    Not Available

    1993-09-01

    The document presents the results of a survey undertaken by the U.S. Environmental Protection Agency's (EPA's) Office of Emergency and Remedial Response (Superfund). The survey was designed to estimate the proportion of National Priorities List (NPL) sites where Dense Nonaqueous Phase Liquids (DNAPLs) may be present. Earlier studies by OERR suggested that DNAPLs may be more common at hazardous waste sites than previously thought, and may act as a continuing source of contamination thus reducing the ability of pump-and-treat systems to attain cleanup goals within expected timeframes (Evaluation of Ground Water Extraction Remedies, Phase II, EPA 9355.4-05). The study represents the first systematic nation-wide review of NPL sites designed to estimate the extent of subsurface DNAPL contamination.

  2. Revegetation and rock cover for stabilization of inactive uranium mill tailings disposal sites. Final report

    SciTech Connect

    Beedlow, P.A.

    1984-05-01

    Guidelines for using vegetation and rock to protect inactive uranium mill tailings from erosion were developed by Pacific Northwest Laboratory as part of the Department of Energy's Uranium Mill Tailings Remedial Action Project (UMTRAP) Technology Development program. Information on soils, climate, and vegetation were collected for 20 inactive tailings sites in the western United States. Sites were grouped according to similarities in climate and vegetation. Soil loss for those sites was characterized using the Universal Soil Loss Equation. Test plots were used to evaluate (1) the interaction between vegetation and sealant barrier systems and (2) the effects of surface rock on soil water and vegetation. Lysimeter and simulation studies were used to direct and support field experiments. 49 references, 17 figures, 16 tables.

  3. PISCES field chemical emissions monitoring project: Site 118 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 118. Site 118 is a residual oil-fired boiler, with an electrostatic precipitator for particulate control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  4. PISCES field chemical emissions monitoring project: Site 14 emissions report. Final report

    SciTech Connect

    1995-11-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 14. Site 14 is a pilot-scale dry flue gas desulfurization (FGD) system consisting of a spray dryer and fabric filter. The flue gas for the pilot unit is provided by an adjacent power plant boiler which bums a medium-sulfur bituminous coal. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency m evaluating utility trace chemical emissions as well as the associated health risk impacts-as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites.

  5. Environmental aspects of the Brandon woods coal ash site. Final report

    SciTech Connect

    Keating, R.W.; Price, R.

    1994-05-01

    The Maryland Power Plant Research Program (PPRP) has evaluated the potential environmental effects of coal ash used as structural fill material at the Baltimore Gas and Electric Company (BG E) Brandon Woods Energy Business Park. The main purpose of the evaluation was to assess the potential for leachate constituents derived from the coal ash to affect ground and surface water quality. Ground water conditions at the site were evaluated using the water level readings collected from 21 shallow and deep monitoring wells installed by BG E prior to site development, and ground water quality data collected from the time the facility began coal ash filling operations in 1982 to December 1990. The absence of ground water quality degradation downgradient of the ash indicates that several site conditions minimize potential adverse enviromental impacts from leachate generation.

  6. Independent Verification Final Summary Report for the David Witherspoon, Inc. 1630 Site Knoxville, Tennessee

    SciTech Connect

    P.C. Weaver

    2009-04-29

    The primary objective of the independent verification was to determine if BJC performed the appropriate actions to meet the specified “hot spot” cleanup criteria of 500 picocuries per gram (pCi/g) uranium-238 (U-238) in surface soil. Specific tasks performed by the independent verification team (IVT) to satisfy this objective included: 1) performing radiological walkover surveys, and 2) collecting soil samples for independent analyses. The independent verification (IV) efforts were designed to evaluate radioactive contaminants (specifically U-238) in the exposed surfaces below one foot of the original site grade, given that the top one foot layer of soil on the site was removed in its entirety.

  7. Nature of airborne particulates at tropic exposure sites. Final report, November 1982-September 1984

    SciTech Connect

    Chen, F.; Dement, W.A.

    1984-09-01

    Airborne particulates were collected at five exposure sites in Panama using cascade impactor air samplers. Scanning electron microscopy, energy dispersive x-ray analysis, and culture identification techniques were used to analyze the particulates. Analysis revealed that the particulates consist of silicates, chlorides, and sulfur-rich and phosphorus-rich particles. Atmospheric particle levels were higher in the dry season than in the rainy season, and the predominant fungal species varied at each exposure site. The open direct exposure of culture plates served as a simple, appropriate method for monitoring atmospheric fungal spores.

  8. Superfund Record of Decision (EPA Region 5): Burrows Sanitation Site, Hartford, Van Buren County, Michigan, September 1986. Final report

    SciTech Connect

    Not Available

    1986-09-30

    The Burrows Sanitation site is a ten-acre site located on 54th Avenue in Hartford Township, Van Buren County, Michigan. The site was used for dewatering and disposing of metal hydroxide sludges, waste coolants, and soluble oils. Sampling of these areas indicates that the former source materials were removed so they no longer present a potential health threat via direct contact or ingestion. Wastes similar to the excavated wastes remain in the newly identified Spill Area No. 2. Principal contaminants include chromium, copper, lead, nickel, zinc, and cyanide. Test results also indicate that the surface water and sediments in the Northwest Wetland and drainage canal have been impacted by the site. In addition, onsite monitoring wells indicate a limited chemical plume or plumes related to site activities.

  9. 77 FR 16558 - General Management Plan/Final Environmental Impact Statement, Hampton National Historic Site...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-03-21

    .... Baltimore County Tourism Office and Towson Chamber of Commerce, 44 West Chesapeake Avenue, Towson, Maryland... review from October 11, 2010, through December 24, 2010. Printed copies of the Draft GMP/EIS were... responses are provided on page 135 of the Final GMP/EIS. After careful review of all comments...

  10. Field Performance Of A Compacted Clay Landfill Final Cover At A Humid Site

    EPA Science Inventory

    A study was conducted in southern Georgia, USA, to evalaute how the hydraulic properties of the compacted clay barrier layer in a final landfill cover changed over a 4-year service life. The cover was part of a test section constructed in a large drainage lysimeter that allowed ...

  11. 78 FR 75913 - Final Tank Closure and Waste Management Environmental Impact Statement for the Hanford Site...

    Federal Register 2010, 2011, 2012, 2013, 2014

    2013-12-13

    ... Alternatives 2 through 6 and the sub- alternatives within them, the contents of the cesium (Cs) and strontium... the Final TC&WM EIS: additional tank waste storage capacity, dry storage of cesium and strontium... cesium and strontium capsules in this ROD; when DOE is ready to make a decision, it will conduct...

  12. Superfund Record of Decision (EPA Region 1): Stamina Mills site, North Smithfield, RI. (First remedial action), September 1990. Final report

    SciTech Connect

    Not Available

    1990-09-28

    The five-acre Stamina Mills site is a former textile weaving and finishing facility in North Smithfield, Providence County, Rhode Island. A portion of the site is within the 100-year floodplain and wetland area of the Branch River. The manufacturing process used cleaning solvents, acids, bases and dyes for coloring, pesticides for moth proofing, and plasticizers to coat fabrics. Mill process wastes were placed in a landfill onsite. EPA initiated three removal actions from 1984 to 1990, including an extension of the municipal water supply to residents obtaining water from the affected aquifer; and treatment of two underground and one above-ground storage tanks, followed by offsite disposal. The Record of Decision (ROD) provides a final remedy and addresses both source control and management of contaminated ground water migration at the site. The primary contaminants of concern affecting the soil, debris, sediment, and ground water are VOCs including TCE and PCE; other organics including pesticides; and metals including chromium.

  13. Identification of covalent active site inhibitors of dengue virus protease

    PubMed Central

    Koh-Stenta, Xiaoying; Joy, Joma; Wang, Si Fang; Kwek, Perlyn Zekui; Wee, John Liang Kuan; Wan, Kah Fei; Gayen, Shovanlal; Chen, Angela Shuyi; Kang, CongBao; Lee, May Ann; Poulsen, Anders; Vasudevan, Subhash G; Hill, Jeffrey; Nacro, Kassoum

    2015-01-01

    Dengue virus (DENV) protease is an attractive target for drug development; however, no compounds have reached clinical development to date. In this study, we utilized a potent West Nile virus protease inhibitor of the pyrazole ester derivative class as a chemical starting point for DENV protease drug development. Compound potency and selectivity for DENV protease were improved through structure-guided small molecule optimization, and protease-inhibitor binding interactions were validated biophysically using nuclear magnetic resonance. Our work strongly suggests that this class of compounds inhibits flavivirus protease through targeted covalent modification of active site serine, contrary to an allosteric binding mechanism as previously described. PMID:26677315

  14. Proposed plan/Statement of basis for the Grace Road Site (631-22G) operable unit: Final action

    SciTech Connect

    Palmer, E.

    1997-08-19

    This Statement of Basis/Proposed Plan is being issued by the U. S. Department of Energy (DOE), which functions as the lead agency for the Savannah River Site (SRS) remedial activities, with concurrence by the U. S. Environmental Protection Agency (EPA), and the South Carolina Department of Health and Environmental Control (SCDHEC). The purpose of this Statement of Basis/Proposed Plan is to describe the preferred alternative for addressing the Grace Road site (GRS) located at the Savannah River Site (SRS), in Aiken, South Carolina and to provide an opportunity for public input into the remedial action selection process.

  15. Final environmental impact assessment of the Paducah Gaseous Diffusion Plant site, Paducah, Kentucky

    SciTech Connect

    Not Available

    1982-08-01

    This document considers: the need for uranium enrichment facilities; site location; plant description; and describes the power generating facilities in light of its existing environment. The impacts from continuing operations are compared with alternatives of shutdown, relocation, and alternative power systems. (PSB)

  16. SUPERFUND TREATABILITY CLEARINGHOUSE: FINAL REPORT: SOIL TREATMENT PILOT STUDY BRIO/DOP SITE

    EPA Science Inventory

    Bench and pilot-scale studies were conducted to demonstrate the feasibility of using solid-phase biodegradation for destroying portions of organic constituents present in the soil. The predominant constituents at the BRIO DOP site located in Texas were volatile compounds such...

  17. Final Report, FY 2001 200 East Vadose Test Site Hanford Washington Electrical Resistance Tomography

    SciTech Connect

    Ramirez, A.; Daily, W.; Binley, A.

    2001-06-30

    This report covers the electrical resistance tomography (ERT) work performed at the Hanford Reservation, 200 East Area Vadose test (Sisson and Lu) site during the period March 23 through May 5,2001. The purposes of the ERT work were to: (1) Compare and contrast the development of the highly concentrated sodium thiosulfate plume (FY 01 work) with the fresh river water plume observed during FY 00. (2) Use the resistance images to infer the dynamics of the plume during two or three of the sodium thio-sulfate releases and during the water ''chaser'' release. (3) Determine the influence of the site's steel casings on the ability to construct reliable ERT images. (4) Determine if the steel casings at the site can be used as long electrodes to provide useful images of at least one release. (5) Develop quantitative estimates of the noise in the data and its effect on reconstructed images. Eleven electrode arrays (nine electrodes arrays available for the FY00 work), each with 15 electrodes, were installed at the site. These were used to perform 3D surveys before, during, and after 3 different spills.

  18. EPA Finalizes Changes to Plan for Groundwater Remediation at Superfund Site in Newfield, N.J.

    EPA Pesticide Factsheets

    (New York, N.Y.) The U.S. Environmental Protection Agency has modified its plan to address contaminated groundwater at the Shieldalloy Metallurgical Corp. site in Newfield and Vineland, N.J. A plan originally put into place in 1996 by the New Jersey Depart

  19. PISCES field chemical emissions monitoring project: Site 119 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 119. Site 119 is a residual oil-fired boiler, with an electrostatic precipitator for particulate control. Site 119 employs close-coupled overfire air and burner modifications for NO{sub x} control. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  20. Final Report: Pilot Region-Based Optimization Program for Fund-Lead Sites, EPA Region III

    EPA Pesticide Factsheets

    This report describes a pilot study for a Region-based optimization program, implemented by a Regional Optimization Evaluation Team (ROET) that was conducted in U.S. EPA Region III at Fund-lead sites with pump-and-treat (P&T) systems.

  1. PISCES Field Chemical Emissions Monitoring Project: Site 18 emissions report. Final report

    SciTech Connect

    1995-11-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 18. Site 18 is a pulverized coal-fired boiler burning a medium-sulfur bituminous coal. Site 18 employs electrostatic precipitators for particulate control. During the sampling project, a pilot pulse-jet fabric filter treated a small fraction of the flue gas downstream of the ESP. Measurements were also conducted around the pilot fabric filter. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts -- as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  2. PISCES field chemical emissions monitoring project: Site 116 emissions report. Final report

    SciTech Connect

    1995-12-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 116. Site 116 consists of a pulverized coal-fired boiler burning a bituminous coal, with an electrostatic precipitator for particulate control. Site 116 also included s a Babcock & Wilcox`s DOE Clean Coal Technology Program`s 5{minus}MWe SO{sub x}{minus}NO{sub x}-Rox Box {trademark} (SNRB{trademark}) Field Demonstration. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts-as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites.

  3. 10 CFR 52.39 - Finality of early site permit determinations.

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ...; or (v) Any significant environmental issue that was not resolved in the early site permit proceeding... necessary based on an update under paragraph (b) of this section; or (iv) Issues a variance requested under..., contentions on the following matters may be litigated in the same manner as other issues material to...

  4. Technical procedures for land use, Deaf Smith County site, Texas: Environmental Field Program: Final draft

    SciTech Connect

    Not Available

    1987-09-01

    This volume contains Technical Procedures pursuant to the Land Use Site Study Plan including land use data acquisition, land use/land cover map compilation, verification of land use/land cover map accuracy, and land use/land cover data analysis. 22 refs., 5 figs.

  5. Active Site Structures in Nitrogen-Doped Carbon-Supported Cobalt Catalysts for the Oxygen Reduction Reaction.

    PubMed

    Qian, Yingdan; Liu, Zheng; Zhang, Hui; Wu, Ping; Cai, Chenxin

    2016-12-07

    The catalytic mechanism and the nature of active sites are revealed for the oxygen reduction reaction (ORR) with new non-noble-metal nitrogen-doped carbon-supported transition-metal catalysts (metal-N-C catalyst). Specifically, new nitrogen-doped carbon-supported cobalt catalysts (Co-N-C catalysts) are made by pyrolyzing various ratios of the nitrogen-atom rich heterocycle compound, 1-ethyl-3-methyl imidazolium dicyanamide (EMIM-dca) and cobalt salt (Co(NO3)2). The ORR activity (JK at 0.8 V vs RHE, in 0.1 M KOH solution) of a typical catalyst in this family, Co15-N-C800, is 8.25 mA/mg, which is much higher than the ORR activity values of N-C catalysts (0.41 mA/mg). The active site in the catalyst is found to be the Co-N species, which is most likely in the form of Co2N. Metallic cobalt (Co) particles, Co3C species, and N-C species are not catalytically active sites, nor do these moieties interact with the Co-N active sites during the catalysis of the ORR. Increasing the Co salt content during the synthesis favors the formation of Co-N active sites in the final catalyst. Higher pyrolysis temperatures (e.g., a temperature higher than 800 °C) do not favor the formation of the Co-N active sites, but cause the formed Co-N active sites to decompose, which, therefore, leads to a lower catalytic activity. This reveals that the control of the parameters that affect the final structure is critical to catalyst performance and, therefore, the effective development of high-performance heteroatom-doped non-noble-metal ORR catalysts.

  6. Multi-agency radiation survey and site investigation manual (MARSIM). Final report

    SciTech Connect

    1997-12-01

    The MARSSIM provides information on planning, conducting, evaluating, and documenting building surface and surface soil final status radiological surveys for demonstrating compliance with dose or risk-based regulations or standards. The MARSSIM is a multi-agency consensus document that was developed collaboratively by four Federal agencies having authority and control over radioactive materials: Department of Defense (DOD), Department of Energy (DOE), Environmental Protection Agency (EPA), and Nuclear Regulatory Commission (NRC). The MARSSIM`s objective is to describe a consistent approach for planning, performing, and assessing building surface and surface soil final status surveys to meet established dose or risk-based release criteria, while at the same time encouraging an effective use of resources.

  7. Experimental Civilian Personnel Office Project (EXPO): Final Report for Appropriated Fund Sites

    DTIC Science & Technology

    1994-01-01

    staff. Finally, the Chief said that it would be very unlikely that there would be a big rush to reclassify jobs under DCA if working relationships...hour, 40 minutes PROCLASS (Short Version) 36 minutes I Air Force Software 54 minutes Not. CPPP = Civilian Position and Performance Program. 3 aData based...had reaped big benefits in terms of time savings and a very positive, cooperative relationship with the Classification Staff. A few managers who were

  8. Target-classification approach applied to active UXO sites

    NASA Astrophysics Data System (ADS)

    Shubitidze, F.; Fernández, J. P.; Shamatava, Irma; Barrowes, B. E.; O'Neill, K.

    2013-06-01

    This study is designed to illustrate the discrimination performance at two UXO active sites (Oklahoma's Fort Sill and the Massachusetts Military Reservation) of a set of advanced electromagnetic induction (EMI) inversion/discrimination models which include the orthonormalized volume magnetic source (ONVMS), joint diagonalization (JD), and differential evolution (DE) approaches and whose power and flexibility greatly exceed those of the simple dipole model. The Fort Sill site is highly contaminated by a mix of the following types of munitions: 37-mm target practice tracers, 60-mm illumination mortars, 75-mm and 4.5'' projectiles, 3.5'', 2.36'', and LAAW rockets, antitank mine fuzes with and without hex nuts, practice MK2 and M67 grenades, 2.5'' ballistic windshields, M2A1-mines with/without bases, M19-14 time fuzes, and 40-mm practice grenades with/without cartridges. The site at the MMR site contains targets of yet different sizes. In this work we apply our models to EMI data collected using the MetalMapper (MM) and 2 × 2 TEMTADS sensors. The data for each anomaly are inverted to extract estimates of the extrinsic and intrinsic parameters associated with each buried target. (The latter include the total volume magnetic source or NVMS, which relates to size, shape, and material properties; the former includes location, depth, and orientation). The estimated intrinsic parameters are then used for classification performed via library matching and the use of statistical classification algorithms; this process yielded prioritized dig-lists that were submitted to the Institute for Defense Analyses (IDA) for independent scoring. The models' classification performance is illustrated and assessed based on these independent evaluations.

  9. TOSPAC calculations in support of the COVE 2A benchmarking activity; Yucca Mountain Site Characterization Project

    SciTech Connect

    Gauthier, J.H.; Zieman, N.B.; Miller, W.B.

    1991-10-01

    The purpose of the the Code Verification (COVE) 2A benchmarking activity is to assess the numerical accuracy of several computer programs for the Yucca Mountain Site Characterization Project of the Department of Energy. This paper presents a brief description of the computer program TOSPAC and a discussion of the calculational effort and results generated by TOSPAC for the COVE 2A problem set. The calculations were performed twice. The initial calculations provided preliminary results for comparison with the results from other COVE 2A participants. TOSPAC was modified in response to the comparison and the final calculations included a correction and several enhancements to improve efficiency. 8 refs.

  10. How Force Might Activate Talin's Vinculin Binding Sites: SMD Reveals a Structural Mechanism

    PubMed Central

    Hytönen, Vesa P; Vogel, Viola

    2008-01-01

    Upon cell adhesion, talin physically couples the cytoskeleton via integrins to the extracellular matrix, and subsequent vinculin recruitment is enhanced by locally applied tensile force. Since the vinculin binding (VB) sites are buried in the talin rod under equilibrium conditions, the structural mechanism of how vinculin binding to talin is force-activated remains unknown. Taken together with experimental data, a biphasic vinculin binding model, as derived from steered molecular dynamics, provides high resolution structural insights how tensile mechanical force applied to the talin rod fragment (residues 486–889 constituting helices H1–H12) might activate the VB sites. Fragmentation of the rod into three helix subbundles is prerequisite to the sequential exposure of VB helices to water. Finally, unfolding of a VB helix into a completely stretched polypeptide might inhibit further binding of vinculin. The first events in fracturing the H1–H12 rods of talin1 and talin2 in subbundles are similar. The proposed force-activated α-helix swapping mechanism by which vinculin binding sites in talin rods are exposed works distinctly different from that of other force-activated bonds, including catch bonds. PMID:18282082

  11. Solar-collector-materials exposure to the IPH site environment. Volume 1. Final report

    SciTech Connect

    Morris, V.L.

    1982-01-01

    In-situ environmental exposure tests were conducted at nine proposed intermediate-temperature Industrial Process Heat (IPH) sites. Three types of reflector materials were evaluated for survivability at the nine sites: second-surface silvered glass, aluminized acrylic FEK-244 film on aluminumsubstrate and Alzak (electropolished aluminum) on aluminium substrate. Black chrome absorber material and low-iron float glass were evaluated for thermal, photochemical, and environmental degradation. The reflector specimens were monitored for decreases in specular and hemispherical reflectance due to soil buildup. The absorber material was evaluated for changes in solar absorptivity and emissivity, and the float glass was monitored for changes in transmissivity. Surface and subsurface defects on all materials were examined microscopically and, where deemed of note, were documented photographically.

  12. Solar-collector materials exposure to the IPH site environment. Final report

    SciTech Connect

    Morris, V.L.

    1982-01-01

    In-situ environmental exposure tests were conducted at nine proposed intermediate-temperature Industrial Process Heat (IPH) sites. Three types of reflector materials were evaluated for survivability at the nine sites: second-surface silvered glass, aluminized acrylic FEK-244 film on aluminum substrate, and Alzak (electropolished aluminum) on aluminum substrate. Black chrome absorber material and low-iron float glass were evaluated for thermal, photochemical, and environmental degradation. The reflector specimens were monitored for decreases in specular and hemispherical reflectance due to soil buildup. The absorber material was evaluated for changes in solar absorptivity and emissivity, and the float glass was monitored for changes in transmissivity. Surface and subsurface defects on all materials were examined microscopically and, where deemed of note, were documented photographically.

  13. Superfund record of decision (EPA Region 4): New Hanover County Airport Burn Pit Site, New Hanover County, Wilmington, NC. (First remedial action), September 1992. Final report

    SciTech Connect

    Not Available

    1992-09-29

    The New Hanover site was located on Gardner Road approximately 500 feet west of the New Hanover County Airport terminal, New Hanover, North Carolina. From 1968 to 1979, the site was used for fire-fighter training purposes. During training exercises, jet fuel, gasoline, petroleum storage bottoms, fuel oil, kerosene, and sorbent materials from oil spill cleanup were burned in a pit. During its active years, water from the pit was allowed to flow onto land surfaces. Inspections conducted after the pit was abandoned showed that most of the standing liquid in the pit was water. In addition to the burn pit area, fire-fighting activities resulted in contamination at several other site areas, including an auto burn area; a railroad tank burn area; an aircraft mock-up area; a fuel tank and pipelines area; and two stained soil areas north of the burn pit. The ROD addressed restoration of the aquifer to drinking water quality as a final action for the site. The primary contaminants of concern that affect the soil and ground water were VOCs, including benzene; and metals, including chromium and lead.

  14. Identification of Phosphorylation Sites Altering Pollen Soluble Inorganic Pyrophosphatase Activity.

    PubMed

    Eaves, Deborah J; Haque, Tamanna; Tudor, Richard L; Barron, Yoshimi; Zampronio, Cleidiane G; Cotton, Nicholas P J; de Graaf, Barend H J; White, Scott A; Cooper, Helen J; Franklin, F Christopher H; Harper, Jeffery F; Franklin-Tong, Vernonica E

    2017-03-01

    Protein phosphorylation regulates numerous cellular processes. Identifying the substrates and protein kinases involved is vital to understand how these important posttranslational modifications modulate biological function in eukaryotic cells. Pyrophosphatases catalyze the hydrolysis of inorganic phosphate (PPi) to inorganic phosphate Pi, driving biosynthetic reactions; they are essential for low cytosolic inorganic phosphate. It was suggested recently that posttranslational regulation of Family I soluble inorganic pyrophosphatases (sPPases) may affect their activity. We previously demonstrated that two pollen-expressed sPPases, Pr-p26.1a and Pr-p26.1b, from the flowering plant Papaver rhoeas were inhibited by phosphorylation. Despite the potential significance, there is a paucity of data on sPPase phosphorylation and regulation. Here, we used liquid chromatographic tandem mass spectrometry to map phosphorylation sites to the otherwise divergent amino-terminal extensions on these pollen sPPases. Despite the absence of reports in the literature on mapping phosphorylation sites on sPPases, a database survey of various proteomes identified a number of examples, suggesting that phosphorylation may be a more widely used mechanism to regulate these enzymes. Phosphomimetic mutants of Pr-p26.1a/b significantly and differentially reduced PPase activities by up to 2.5-fold at pH 6.8 and 52% in the presence of Ca(2+) and hydrogen peroxide over unmodified proteins. This indicates that phosphoregulation of key sites can inhibit the catalytic responsiveness of these proteins in concert with key intracellular events. As sPPases are essential for many metabolic pathways in eukaryotic cells, our findings identify the phosphorylation of sPPases as a potential master regulatory mechanism that could be used to attenuate metabolism.

  15. Evidence for segmental mobility in the active site of pepsin

    SciTech Connect

    Pohl, J.; Strop, P.; Senn, H.; Foundling, S.; Kostka, V.

    1986-05-01

    The low hydrolytic activity (k/sub cat/ < 0.001 s/sup -1/) of chicken pepsin (CP) towards tri- and tetrapeptides is enhanced at least 100 times by modification of its single sulfhydryl group of Cys-115, with little effect on K/sub m/-values. Modification thus simulates the effect of secondary substrate binding on pepsin catalysis. The rate of Cys-115 modification is substantially decreased in the presence of some competitive inhibitors, suggesting its active site location. Experiments with CP alkylated at Cys-115 with Acrylodan as a fluorescent probe or with N-iodoacetyl-(4-fluoro)-aniline as a /sup 19/F-nmr probe suggest conformation change around Cys-115 to occur on substrate or substrate analog binding. The difference /sup 1/H-nmr spectra (500 MHz) of unmodified free and inhibitor-complexed CP reveal chemical shifts almost exclusively in the aromatic region. The effects of Cu/sup + +/ on /sup 19/F- and /sup 1/H-nmr spectra have been studied. Examination of a computer graphics model of CP based on E. parasitica pepsin-inhibitor complex X-ray coordinates suggests that Cys-115 is located near the S/sub 3//S/sub 5/ binding site. The results are interpreted in favor of segmental mobility of this region important for pepsin substrate binding and catalysis.

  16. Analytic study to evaluate associations between hazardous waste sites and birth defects. Final report

    SciTech Connect

    Marshall, E.G.; Gensburg, L.J.; Geary, N.S.; Deres, D.A.; Cayo, M.R.

    1995-06-01

    A study was conducted to evaluate the risk of two types of birth defects (central nervous system and musculoskeletal defects) associated with mothers` exposure to solvents, metals, and pesticides through residence near hazardous waste sites. The only environmental factor showing a statistically significant elevation in risk was living within one mile of industrial or commercial facilities emitting solvents into the air. Residence near these facilities showed elevated risk for central nervous system defects but no elevated risks for musculoskeletal defects.

  17. Barometric pressure transient testing applications at the Nevada Test Site: formation permeability analysis. Final report

    SciTech Connect

    Hanson, J.M.

    1984-12-01

    The report evaluates previous investigations of the gas permeability of the rock surrounding emplacement holes at the Nevada Test Site. The discussion sets the framework from which the present uncertainty in gas permeability can be overcome. The usefulness of the barometric pressure testing method has been established. Flow models were used to evaluate barometric pressure transients taken at NTS holes U2fe, U19ac and U20ai. 31 refs., 103 figs., 18 tabs. (ACR)

  18. Technical procedures for ecology: Environmental field program, Deaf Smith County Site, Texas: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    This volume contains Technical Procedures pursuant to the Land Use Site Study Plan including walkover surveys for threatened, endangered, or candidate species; vegetation classification and mapping; reclamation planning; wetland and floodplain determination and characterization of playas; wildlife habitat mapping methods; mammal sampling; bird survey methods; reptile and amphibian survey methods; preexisting environmental; stress and disturbance studies methods; voucher specimens for plants; and voucher specimens to wildlife. 9 refs., 5 figs., 1 tab.

  19. 77 FR 56714 - Agency Information Collection (Annual-Final Report and Account) Activities Under OMB Review

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-13

    ... Information Collection (Annual-Final Report and Account) Activities Under OMB Review AGENCY: Veterans Benefits... . Please refer to ``OMB Control No. 2900-0017.'' SUPPLEMENTARY INFORMATION: Titles: a. Annual-Final Report.... Estimated Annual Burden: a. Annual-Final Report and Account, VA Form 21-4706--1,100. b. Federal......

  20. 77 FR 39341 - Proposed Information Collection (Annual-Final Report and Account) Activity: Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-07-02

    ... AFFAIRS Proposed Information Collection (Annual-Final Report and Account) Activity: Comment Request AGENCY.... Annual-Final Report and Account, VA Form 21-4706. b. Federal Fiduciary's Account, VA Form 21-4706b. c.... Estimated Annual Burden: a. Annual-Final Report and Account, VA Form 21-4706--1,100. b. Federal...

  1. Learning to forecast wind at remote sites for wind energy applications. Final report

    SciTech Connect

    Notis, C.; Trettel, D.W.; Aquino, J.T.; Piazza, T.R.; Taylor, L.E.; Trask, D.C.; Wegley, H.L.; Miller, A.H.

    1983-01-01

    Observed wind patterns are correlated with synoptic or mescoscale weather systems. Six sites selected for analysis include Montauk Point, New York; Boone, North Carolina; Ludington, Michigan; Clayton, New Mexico; Amarillo, Texas; and San Gorgonio Pass, California. Objectives of the analysis are: to identify synoptic and/or mesoscale weather patterns that are associated with recognizable wind events at the sites; to define a set of criteria that uniquely describes such weather patterns; to estimate the reliability (accuracy) of forecasting rules derived from the association of weather patterns and site winds; and to attempt to separate any mesoscale effects of local topography from the synoptic-scale effects. One-to-one mapping of wind regimes onto synoptic types was not found. It was concluded that four factors should be examined when stratifying wind regimes: synoptic situation, descriptive climatology, pressure gradient vector, and winds aloft. The wind forecasting approach developed was intended for forecasting hourly average winds out to the 24 hour or possibly 36 hour time horizon. (LEW)

  2. Conceptual model for regional radionuclide transport from a basalt repository site. Final draft, technical memorandum

    SciTech Connect

    Walton, W.C.; Voorhees, M.L.; Prickett, T.A.

    1980-05-23

    This technical memorandum was prepared to: (1) describe a typical basalt radionuclide repository site, (2) describe geologic and hydrologic processes associated with regional radionuclide transport in basalts, (3) define the parameters required to model regional radionuclide transport from a basalt repository site, and (4) develop a ''conceptual model'' of radionuclide transport from a basalt repository site. In a general hydrological sense, basalts may be described as layered sequences of aquifers and aquitards. The Columbia River Basalt, centered near the semi-arid Pasco Basin, is considered by many to be typical basalt repository host rock. Detailed description of the flow system including flow velocities with high-low hydraulic conductivity sequences are not possible with existing data. However, according to theory, waste-transport routes are ultimately towards the Columbia River and the lengths of flow paths from the repository to the biosphere may be relatively short. There are many physical, chemical, thermal, and nuclear processes with associated parameters that together determine the possible pattern of radionuclide migration in basalts and surrounding formations. Brief process descriptions and associated parameter lists are provided. Emphasis has been placed on the use of the distribution coefficient in simulating ion exchange. The use of the distribution coefficient approach is limited because it takes into account only relatively fast mass transfer processes. In general, knowledge of hydrogeochemical processes is primitive.

  3. Pilot-scale incineration of comtaminated soils from the drake chemical superfund site. Final report

    SciTech Connect

    King, C.; Lee, J.W.; Waterland, L.R.

    1993-03-01

    A series of pilot-scale incineration tests were performed at the U.S. Environmental Protection Agency's (EPA's) Incineration Research Facility to evaluate the potential of incineration as an option to treat contaminated soils from the Drake Chemical Superfund site in Lock Haven, Pennsylvania. The soils at the Drake site are reported to be contaminated to varying degrees with various organic constituents and several hazardous constituent trace metals. The purpose of the test program was to evaluate the incinerability of selected site soils in terms of the destruction of contaminant organic constituents and the fate of contaminant trace metals. All tests were conducted in the rotary kiln incineration system at the IRF. Test results show that greater than 99.995 percent principal organic hazardous constituent (POHC) destruction and removal efficiencies (DRE) can be achieved at kiln exit gas temperatures of nominally 816 C (1,500 F) and 538 C (1,000 F). Complete soil decontamination of semivolatile organics was achieved; however, kiln ash levels of three volatile organic constituents remained comparable to soil levels.

  4. PISCES field chemical emissions monitoring project: Site 13 emissions report. Final report

    SciTech Connect

    1995-11-01

    This report is one of a series sponsored by the Electric Power Research Institute in the area of trace substance emissions from fossil-fuel power plants. This report presents the results of a sampling and analytical study to characterize trace substances emissions at Site 13. Site 13 consists of a boiler burning No. 6 fuel oil. No air pollution control equipment was available to control emissions from the boiler; however, a pilot-scale pulse-jet fabric filter treating a small fraction of the flue gas from this unit was also tested. The objective of this report is to transmit the detailed data to the US Environmental Protection Agency (EPA) to assist the Agency in evaluating utility trace chemical emissions as well as the associated health risk impacts--as mandated in Title III of the 1990 Clean Air Act Amendments. This report does not attempt to compare the results with other sites. An assessment of data from all plants that have been tested is presented in the Electric Utility Trace Substances Synthesis Report (EPRI TR-104614).

  5. Final Clean Closure Report Site 300 Surface Impoundments Closure Lawrence Livermore National Laboratory Livermore, California

    SciTech Connect

    Haskell, K

    2006-02-14

    Lawrence Livermore National Laboratory operated two Class II surface impoundments that stored wastewater that was discharged from a number of buildings located on the Site 300 Facility (Site 300). The wastewater was the by-product of explosives processing. Reduction in the volume of water discharged from these buildings over the past several years significantly reduced the wastewater storage needs. In addition, the impoundments were constructed in 1984, and the high-density polyethylene (HDPE) geomembrane liners were nearing the end of their service life. The purpose of this project was to clean close the surface impoundments and provide new wastewater storage using above ground storage tanks at six locations. The tanks were installed and put into service prior to closure of the impoundments. This Clean Closure Report (Closure Report) complies with State Water Resources Control Board (SWRCB) Section 21400 of the California Code of Regulations Title 27 (27 CCR section 21400). As required by these regulations and guidance, this Closure Report provides the following information: (1) a brief site description; (2) the regulatory requirements relevant to clean closure of the impoundments; (3) the closure procedures; and (4) the findings and documentation of clean closure.

  6. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Mexican Hat, Utah: Appendix E. Final report

    SciTech Connect

    1988-07-01

    This document provides Appendix E of the Remedial Action Plan (RAP) presented in 1988 for the stabilization of the inactive uranium mill tailings at the Mexican Hat, Utah site. The RAP was developed to serve a two- fold purpose. It presents the activities proposed by the Department of Energy (DOE) to accomplish long-term stabilization and control of the residual radioactive materials (RRM) from Monument Valley, Arizona, and Mexican Hat, Utah, at the Mexican Hat disposal site. It also serves to document the concurrence of both the Navajo Nation and the Nuclear Regulatory Commission (NRC) in the remedial action. This agreement, upon execution by the DOE and the Navajo Nation and concurrence by the NRC, becomes Appendix B of the Cooperative Agreement. The RAP has been structured to provide a comprehensive understanding of the remedial action proposed for the Monument Valley and Mexican Hat sites. It includes specific design and construction requirements for the remedial action.

  7. C-H Activation on Co,O Sites: Isolated Surface Sites versus Molecular Analogs.

    PubMed

    Estes, Deven P; Siddiqi, Georges; Allouche, Florian; Kovtunov, Kirill V; Safonova, Olga V; Trigub, Alexander L; Koptyug, Igor V; Copéret, Christophe

    2016-11-16

    The activation and conversion of hydrocarbons is one of the most important challenges in chemistry. Transition-metal ions (V, Cr, Fe, Co, etc.) isolated on silica surfaces are known to catalyze such processes. The mechanisms of these processes are currently unknown but are thought to involve C-H activation as the rate-determining step. Here, we synthesize well-defined Co(II) ions on a silica surface using a metal siloxide precursor followed by thermal treatment under vacuum at 500 °C. We show that these isolated Co(II) sites are catalysts for a number of hydrocarbon conversion reactions, such as the dehydrogenation of propane, the hydrogenation of propene, and the trimerization of terminal alkynes. We then investigate the mechanisms of these processes using kinetics, kinetic isotope effects, isotopic labeling experiments, parahydrogen induced polarization (PHIP) NMR, and comparison with a molecular analog. The data are consistent with all of these reactions occurring by a common mechanism, involving heterolytic C-H or H-H activation via a 1,2 addition across a Co-O bond.

  8. Polarizability of the active site of cytochrome c reduces the activation barrier for electron transfer

    PubMed Central

    Dinpajooh, Mohammadhasan; Martin, Daniel R.; Matyushov, Dmitry V.

    2016-01-01

    Enzymes in biology’s energy chains operate with low energy input distributed through multiple electron transfer steps between protein active sites. The general challenge of biological design is how to lower the activation barrier without sacrificing a large negative reaction free energy. We show that this goal is achieved through a large polarizability of the active site. It is polarized by allowing a large number of excited states, which are populated quantum mechanically by electrostatic fluctuations of the protein and hydration water shells. This perspective is achieved by extensive mixed quantum mechanical/molecular dynamics simulations of the half reaction of reduction of cytochrome c. The barrier for electron transfer is consistently lowered by increasing the number of excited states included in the Hamiltonian of the active site diagonalized along the classical trajectory. We suggest that molecular polarizability, in addition to much studied electrostatics of permanent charges, is a key parameter to consider in order to understand how enzymes work. PMID:27306204

  9. Active Sites Environmental Monitoring Program: Program plan. Revision 1

    SciTech Connect

    Ashwood, T.L.; Wickliff, D.S.; Morrissey, C.M.

    1992-02-01

    The Active Sites Environmental Monitoring Program (ASEMP), initiated in 1989, provides early detection and performance monitoring of transuranic (TRU) waste and active low-level waste (LLW) facilities at Oak Ridge National Laboratory (ORNL) in accordance with US Department of Energy (DOE) Order 5820.2A. Active LLW facilities in Solid Waste Storage Area (SWSA) 6 include Tumulus I and Tumulus II, the Interim Waste Management Facility (IWMF), LLW silos, high-range wells, asbestos silos, and fissile wells. The tumulus pads and IWMF are aboveground, high-strength concrete pads on which concrete vaults containing metal boxes of LLW are placed; the void space between the boxes and vaults is filled with grout. Eventually, these pads and vaults will be covered by an engineered multilayered cap. All other LLW facilities in SWSA 6 are below ground. In addition, this plan includes monitoring of the Hillcut Disposal Test Facility (HDTF) in SWSA 6, even though this facility was completed prior to the data of the DOE order. In SWSA 5 North, the TRU facilities include below-grade engineered caves, high-range wells, and unlined trenches. All samples from SWSA 6 are screened for alpha and beta activity, counted for gamma-emitting isotopes, and analyzed for tritium. In addition to these analytes, samples from SWSA 5 North are analyzed for specific transuranic elements.

  10. Supporting evaluation for the proposed plan for final remedial action for the groundwater operable unit at the chemical plant area of the Weldon Spring Site, Weldon Spring, Missouri.

    SciTech Connect

    2003-08-06

    This report presents the technical information developed since the interim record of decision (IROD) was issued in September 2000 (U.S. Department of Energy [DOE] 2000). The information was incorporated into the evaluation that was performed in selecting the preferred alternative for the Chemical Plant groundwater operable unit (GWOU) of the Weldon Spring site. The contaminants of concern (COCs) in groundwater and springs are trichloroethylene (TCE), nitrate, uranium, and nitroaromatic compounds. The preferred alternative of monitored natural attenuation (MNA) coupled with institutional controls (ICs) and contingency activities is described in the ''Proposed Plan (PP) for Final Remedial Action for the Groundwater Operable Unit at the Chemical Plant Area of the Weldon Spring Site, Weldon Spring, Missouri'' (DOE 2003b).

  11. Final report on decommissioning of wells, boreholes, and tiltmeter sites, Gulf Coast Interior Salt Domes of Louisiana

    SciTech Connect

    Not Available

    1989-07-01

    In the late 1970s, test holes were drilled in northern Louisiana in the vicinity of Vacherie and Rayburn`s Salt Domes as part of the Department of Energy`s (DOE) National Waste Terminal Storage (NWTS) (rename the Civilian Radioactive Waste Management (CRWM)) program. The purpose of the program was to evaluate the suitability of salt domes for long term storage or disposal of high-level nuclear waste. The Institute for Environmental Studies at Louisiana State University (IES/LSU) and Law Engineering Testing Company (LETCo) of Marietta, Georgia performed the initial field studies. In 1982, DOE awarded a contract to the Earth Technology Corporation (TETC) of Long Beach, California to continue the Gulf Coast Salt Dome studies. In 1986, DOE deferred salt domes from further consideration as repository sites. This report describes test well plugging and site abandonment activities performed by SWEC in accordance with Activity Plan (AP) 1--3, Well Plugging and Site Restoration of Work Sites in Louisiana. The objective of the work outlined in this AP was to return test sites to as near original condition as possible by plugging boreholes, removing equipment, regrading, and seeding. Appendices to this report contain forms required by State of Louisiana, used by SWEC to document decommissioning activities, and pertinent documentation related to lease/access agreements.

  12. Siting a municipal solid waste disposal facility, part II: the effects of external criteria on the final decision.

    PubMed

    Korucu, M Kemal; Karademir, Aykan

    2014-02-01

    The procedure of a multi-criteria decision analysis supported by the geographic information systems was applied to the site selection process of a planning municipal solid waste management practice based on twelve different scenarios. The scenarios included two different decision tree modes and two different weighting models for three different area requirements. The suitability rankings of the suitable sites obtained from the application of the decision procedure for the scenarios were assessed by a factorial experimental design concerning the effect of some external criteria on the final decision of the site selection process. The external criteria used in the factorial experimental design were defined as "Risk perception and approval of stakeholders" and "Visibility". The effects of the presence of these criteria in the decision trees were evaluated in detail. For a quantitative expression of the differentiations observed in the suitability rankings, the ranking data were subjected to ANOVA test after a normalization process. Then the results of these tests were evaluated by Tukey test to measure the effects of external criteria on the final decision. The results of Tukey tests indicated that the involvement of the external criteria into the decision trees produced statistically meaningful differentiations in the suitability rankings. Since the external criteria could cause considerable external costs during the operation of the disposal facilities, the presence of these criteria in the decision tree in addition to the other criteria related to environmental and legislative requisites could prevent subsequent external costs in the first place.

  13. Impact of single-site axonal GABAergic synaptic events on cerebellar interneuron activity

    PubMed Central

    Zorrilla de San Martin, Javier; Jalil, Abdelali

    2015-01-01

    Axonal ionotropic receptors are present in a variety of neuronal types, and their function has largely been associated with the modulation of axonal activity and synaptic release. It is usually assumed that activation of axonal GABAARs comes from spillover, but in cerebellar molecular layer interneurons (MLIs) the GABA source is different: in these cells, GABA release activates presynaptic GABAA autoreceptors (autoRs) together with postsynaptic targets, producing an autoR-mediated synaptic event. The frequency of presynaptic, autoR-mediated miniature currents is twice that of their somatodendritic counterparts, suggesting that autoR-mediated responses have an important effect on interneuron activity. Here, we used local Ca2+ photolysis in MLI axons of juvenile rats to evoke GABA release from individual varicosities to study the activation of axonal autoRs in single release sites. Our data show that single-site autoR conductances are similar to postsynaptic dendritic conductances. In conditions of high [Cl−]i, autoR-mediated conductances range from 1 to 5 nS; this corresponds to ∼30–150 GABAA channels per presynaptic varicosity, a value close to the number of channels in postsynaptic densities. Voltage responses produced by the activation of autoRs in single varicosities are amplified by a Nav-dependent mechanism and propagate along the axon with a length constant of 91 µm. Immunolabeling determination of synapse location shows that on average, one third of the synapses produce autoR-mediated signals that are large enough to reach the axon initial segment. Finally, we show that single-site activation of presynaptic GABAA autoRs leads to an increase in MLI excitability and thus conveys a strong feedback signal that contributes to spiking activity. PMID:26621773

  14. Impact of single-site axonal GABAergic synaptic events on cerebellar interneuron activity.

    PubMed

    de San Martin, Javier Zorrilla; Jalil, Abdelali; Trigo, Federico F

    2015-12-01

    Axonal ionotropic receptors are present in a variety of neuronal types, and their function has largely been associated with the modulation of axonal activity and synaptic release. It is usually assumed that activation of axonal GABA(A)Rs comes from spillover, but in cerebellar molecular layer interneurons (MLIs) the GABA source is different: in these cells, GABA release activates presynaptic GABA(A) autoreceptors (autoRs) together with postsynaptic targets, producing an autoR-mediated synaptic event. The frequency of presynaptic, autoR-mediated miniature currents is twice that of their somatodendritic counterparts, suggesting that autoR-mediated responses have an important effect on interneuron activity. Here, we used local Ca(2+) photolysis in MLI axons of juvenile rats to evoke GABA release from individual varicosities to study the activation of axonal autoRs in single release sites. Our data show that single-site autoR conductances are similar to postsynaptic dendritic conductances. In conditions of high [Cl(-)](i), autoR-mediated conductances range from 1 to 5 nS; this corresponds to ∼30-150 GABA(A) channels per presynaptic varicosity, a value close to the number of channels in postsynaptic densities. Voltage responses produced by the activation of autoRs in single varicosities are amplified by a Na(v)-dependent mechanism and propagate along the axon with a length constant of 91 µm. Immunolabeling determination of synapse location shows that on average, one third of the synapses produce autoR-mediated signals that are large enough to reach the axon initial segment. Finally, we show that single-site activation of presynaptic GABA(A) autoRs leads to an increase in MLI excitability and thus conveys a strong feedback signal that contributes to spiking activity.

  15. Photolytic Destruction Technology demonstration, NAS North Island, Site 9. Final contract report, October 1997--February 1998

    SciTech Connect

    1998-08-01

    The Photolytic Destruction Technology was chosen for demonstration, as part of the Navy Environmental Leadership Program (NELP), at Naval Air Station (NAS) North Island`s Site 9 soil vapor extraction (SVE) system. The demonstration was conducted, under contract N47408-97-C-0215 through Naval Facilities Engineering Service Center`s Broad Agency Announcement (BAA) program, to Process Technologies Incorporated (PTI), beginning October 7, 1997 and ending February 12, 1998, for 128 days. The literature search, demonstration oversight, and evaluation were funded by the Pollution Abatement Ashore Program managed by Naval Facilities Engineering Command and sponsored by the Environmental Protection, Safety and Occupational Health Division (N45) of the Chief of Naval Operations. The system was installed to treat a slip stream containing volatile organic compounds (VOCs) from the operating SVE system already installed at the site. The goal of this demonstration was to obtain the necessary cost and performance data, including the lessons learned, on the system comprising of a concentrator, condenser, and photolytic destruction unit (PDU), for comparison with other treatment technologies. The system was demonstrated on air stream contaminated with halogenated and non-halogenated VOCs such as l,2- dichloroethene, trichloroethene, tetrachloroethene, toluene, and octane. The test results indicated that the system was effective in removing VOCs in thc SVE off-gas to below the maximum allowable emissions of 25 parts per million by volume. The average total DRE achieved for VOCs was 95.44% whereas the PDU alone demonstrated an overall DRE of 97%. The estimated unit cost to treat SVE off-gas at NAS North Island`s Site 9, for a 3,000 standard cubic feet per minute PTI system, is $3.77 per pound of VOC treated.

  16. On-site effluent toxicity studies at the Goodyear Atomic Corporation. Final report

    SciTech Connect

    Ferrante, J.G.; Bean, D.J.

    1986-04-01

    Acute on-site, flow-through bioassays were conducted with effluents from outfalls 001 and 002 at the Goodyear Atomic facility in Piketon, Ohio. Data collected during this study indicate that the effluents were not toxic to the two species of fish (creek chub and fathead minnow) and one species of invertebrates (crayfish) used as test organisms. The only evidence of an adverse effect was observed in the response of Daphnia magna to effluent 001, which produced a ''ballooning'' effect in laboratory studies while dilution and laboratory water failed to elicit the same response.

  17. Active Site and Laminarin Binding in Glycoside Hydrolase Family 55*

    PubMed Central

    Bianchetti, Christopher M.; Takasuka, Taichi E.; Deutsch, Sam; Udell, Hannah S.; Yik, Eric J.; Bergeman, Lai F.; Fox, Brian G.

    2015-01-01

    The Carbohydrate Active Enzyme (CAZy) database indicates that glycoside hydrolase family 55 (GH55) contains both endo- and exo-β-1,3-glucanases. The founding structure in the GH55 is PcLam55A from the white rot fungus Phanerochaete chrysosporium (Ishida, T., Fushinobu, S., Kawai, R., Kitaoka, M., Igarashi, K., and Samejima, M. (2009) Crystal structure of glycoside hydrolase family 55 β-1,3-glucanase from the basidiomycete Phanerochaete chrysosporium. J. Biol. Chem. 284, 10100–10109). Here, we present high resolution crystal structures of bacterial SacteLam55A from the highly cellulolytic Streptomyces sp. SirexAA-E with bound substrates and product. These structures, along with mutagenesis and kinetic studies, implicate Glu-502 as the catalytic acid (as proposed earlier for Glu-663 in PcLam55A) and a proton relay network of four residues in activating water as the nucleophile. Further, a set of conserved aromatic residues that define the active site apparently enforce an exo-glucanase reactivity as demonstrated by exhaustive hydrolysis reactions with purified laminarioligosaccharides. Two additional aromatic residues that line the substrate-binding channel show substrate-dependent conformational flexibility that may promote processive reactivity of the bound oligosaccharide in the bacterial enzymes. Gene synthesis carried out on ∼30% of the GH55 family gave 34 active enzymes (19% functional coverage of the nonredundant members of GH55). These active enzymes reacted with only laminarin from a panel of 10 different soluble and insoluble polysaccharides and displayed a broad range of specific activities and optima for pH and temperature. Application of this experimental method provides a new, systematic way to annotate glycoside hydrolase phylogenetic space for functional properties. PMID:25752603

  18. Metal active site elasticity linked to activation of homocysteine in methionine synthases

    SciTech Connect

    Koutmos, Markos; Pejchal, Robert; Bomer, Theresa M.; Matthews, Rowena G.; Smith, Janet L.; Ludwig, Martha L.

    2008-04-02

    Enzymes possessing catalytic zinc centers perform a variety of fundamental processes in nature, including methyl transfer to thiols. Cobalamin-independent (MetE) and cobalamin-dependent (MetH) methionine synthases are two such enzyme families. Although they perform the same net reaction, transfer of a methyl group from methyltetrahydrofolate to homocysteine (Hcy) to form methionine, they display markedly different catalytic strategies, modular organization, and active site zinc centers. Here we report crystal structures of zinc-replete MetE and MetH, both in the presence and absence of Hcy. Structural investigation of the catalytic zinc sites of these two methyltransferases reveals an unexpected inversion of zinc geometry upon binding of Hcy and displacement of an endogenous ligand in both enzymes. In both cases a significant movement of the zinc relative to the protein scaffold accompanies inversion. These structures provide new information on the activation of thiols by zinc-containing enzymes and have led us to propose a paradigm for the mechanism of action of the catalytic zinc sites in these and related methyltransferases. Specifically, zinc is mobile in the active sites of MetE and MetH, and its dynamic nature helps facilitate the active site conformational changes necessary for thiol activation and methyl transfer.

  19. An Active Site Water Network in the Plasminogen Activator Pla from Yersinia pestis

    SciTech Connect

    Eren, Elif; Murphy, Megan; Goguen, Jon; van den Berg, Bert

    2010-08-13

    The plasminogen activator Pla from Yersinia pestis is an outer membrane protease (omptin) that is important for the virulence of plague. Here, we present the high-resolution crystal structure of wild-type, enzymatically active Pla at 1.9 {angstrom}. The structure shows a water molecule located between active site residues D84 and H208, which likely corresponds to the nucleophilic water. A number of other water molecules are present in the active site, linking residues important for enzymatic activity. The R211 sidechain in loop L4 is close to the nucleophilic water and possibly involved in the stabilization of the oxyanion intermediate. Subtle conformational changes of H208 result from the binding of lipopolysaccharide to the outside of the barrel, explaining the unusual dependence of omptins on lipopolysaccharide for activity. The Pla structure suggests a model for the interaction with plasminogen substrate and provides a more detailed understanding of the catalytic mechanism of omptin proteases.

  20. An active site water network in the plasminogen activator pla from Yersinia pestis.

    PubMed

    Eren, Elif; Murphy, Megan; Goguen, Jon; van den Berg, Bert

    2010-07-14

    The plasminogen activator Pla from Yersinia pestis is an outer membrane protease (omptin) that is important for the virulence of plague. Here, we present the high-resolution crystal structure of wild-type, enzymatically active Pla at 1.9 A. The structure shows a water molecule located between active site residues D84 and H208, which likely corresponds to the nucleophilic water. A number of other water molecules are present in the active site, linking residues important for enzymatic activity. The R211 sidechain in loop L4 is close to the nucleophilic water and possibly involved in the stabilization of the oxyanion intermediate. Subtle conformational changes of H208 result from the binding of lipopolysaccharide to the outside of the barrel, explaining the unusual dependence of omptins on lipopolysaccharide for activity. The Pla structure suggests a model for the interaction with plasminogen substrate and provides a more detailed understanding of the catalytic mechanism of omptin proteases.

  1. Linde FUSRAP Site Remediation: Engineering Challenges and Solutions of Remedial Activities on an Active Industrial Facility - 13506

    SciTech Connect

    Beres, Christopher M.; Fort, E. Joseph; Boyle, James D.

    2013-07-01

    The Linde FUSRAP Site (Linde) is located in Tonawanda, New York at a major research and development facility for Praxair, Inc. (Praxair). Successful remediation activities at Linde combines meeting cleanup objectives of radiological contamination while minimizing impacts to Praxair business operations. The unique use of Praxair's property coupled with an array of active and abandoned utilities poses many engineering and operational challenges; each of which has been overcome during the remedial action at Linde. The U.S. Army Corps of Engineers - Buffalo District (USACE) and CABRERA SERVICES, INC. (CABRERA) have successfully faced engineering challenges such as relocation of an aboveground structure, structural protection of an active water line, and installation of active mechanical, electrical, and communication utilities to perform remediation. As remediation nears completion, continued success of engineering challenges is critical as remaining activities exist in the vicinity of infrastructure essential to business operations; an electrical substation and duct bank providing power throughout the Praxair facility. Emphasis on engineering and operations through final remediation and into site restoration will allow for the safe and successful completion of the project. (authors)

  2. Avian Species Inventory at Manzanar National Historic Site, California - Final Report to the National Park Service

    USGS Publications Warehouse

    Hart, Jan; Drost, Charles

    2008-01-01

    We conducted a baseline inventory for avian species at Manzanar National Historic Site, Inyo County, Calif., from 2002 to 2005. Under the guidelines of the Mojave Network Biological Inventory Program, the primary objectives for this study were to (1) inventory and document the occurrence of avian species at Manzanar, with the goal of documenting at least 90 percent of the species present; (2) provide a geographic information system (GIS)-referenced list of sensitive species occurring at Manzanar that are rare, on Federal or State lists, or otherwise worthy of special consideration; and (3) enter all species data into the National Park Service NPSpecies database. Survey methods included general area searches, variable circular plot point-count censusing, nocturnal surveys, and nest searching. During 13 year-round survey sessions, we documented the occurrence of 132 bird species at Manzanar and confirmed breeding by 19 of these. Based on our findings, as well as review of the literature and searches for records of species occurrence, we estimate inventory completeness for regularly occurring bird species at Manzanar to be near 90 percent. No sensitive species on Federal or State lists were found. The distribution and relative abundance of common bird species at this site is now well enough known to begin development of a monitoring protocol for this group.

  3. Environmental assessment for device assembly facility operations, Nevada Test Site, Nye County, Nevada. Final report

    SciTech Connect

    1995-05-01

    The U.S. Department of Energy, Nevada Operations Office (DOE/NV), has prepared an environmental assessment (EA), (DOE/EA-0971), to evaluate the impacts of consolidating all nuclear explosive operations at the newly constructed Device Assembly Facility (DAF) in Area 6 of the Nevada Test Site. These operations generally include assembly, disassembly or modification, staging, transportation, testing, maintenance, repair, retrofit, and surveillance. Such operations have previously been conducted at the Nevada Test Site in older facilities located in Area 27. The DAF will provide enhanced capabilities in a state-of-the-art facility for the safe, secure, and efficient handling of high explosives in combination with special nuclear materials (plutonium and highly enriched uranium). Based on the information and analyses in the EA, DOE has determined that the proposed action would not constitute a major federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act of 1969 (42 U.S.C. 4321 et seq.). Therefore, an environmental impact statement is not required, and DOE is issuing this finding of no significant impact.

  4. Final Environmental Assessment for solid waste disposal, Nevada Test Site, Nye County, Nevada

    SciTech Connect

    1995-08-01

    New solid waste regulations require that the existing Nevada Test Site (NTS) municipal landfills, which receive less than 20 tons of waste per day, be permitted or closed by October 9, 1995. In order to be permitted, the existing landfills must meet specific location, groundwater monitoring, design, operation, and closure requirements. The issuance of these regulations has resulted in the need of the Department of Energy (DOE) to provide a practical, cost-effective, environmentally sound means of solid waste disposal at the NTS that is in compliance with all applicable federal, state, and local regulations. The current landfills in Areas 9 and 23 on the Nevada Test Site do not meet design requirements specified in new state and federal regulations. The DOE Nevada Operations Office prepared an environmental assessment (EA) to evaluate the potential impacts of the proposal to modify the Area 23 landfill to comply with the new regulations and to close the Area 9 landfill and reopen it as Construction and Demolition debris landfill. Based on information and analyses presented in the EA, DOE has determined that the proposed action would not constitute a major federal action significantly affecting the quality of the human environment within the meaning of the National Environmental Policy Act. Therefore, an environmental impact statement (EIS) is not required. This report contains the Environmental Assessment, as well as the Finding of No Significant Impact (FONSI).

  5. Department of Energy Site Operator Program. Final report, October 1, 1991--September 31, 1996

    SciTech Connect

    1996-12-31

    York Technical College is a two-year public institution accredited by the Commission of Colleges of the Southern Association of Colleges and Schools. York Technical College has been involved with electric vehicles since the late 1980`s. The four major objectives of the Site Operator Program were (1) field test and evaluate electric and hybrid vehicles and related components; (2) define and develop a national infrastructure system including electric charging systems, service/training education programs, utility system impacts and safety standards; (3) increase public awareness regarding environmental benefits, reduced dependency on foreign oil, technology development, and economic impacts; (4) assist local, state and federal agencies and fleet operators in developing electric and hybrid vehicle programs. The primary thrusts of the electric vehicle program at York Technical College, supporting the objectives of the Site Operator program were: (1) public awareness, (2) public education, (3) EV maintenance curriculum development and maintenance training, (4) field data collection, (5) vehicle modification and upgrade, (6) establish electric vehicle partnerships.

  6. Cometabolic bioreactor demonstration at the Oak Ridge K-25 Site: Final report

    SciTech Connect

    Lucero, A.J.; Donaldson, T.L.; Jennings, H.L.; Morris, M.I.; Palumbo, A.V.; Herbes, S.E.

    1995-08-01

    The Oak Ridge National Laboratory (ORNL) conducted a demonstration of cometabolic technology for bioremediation of groundwater contaminated with trichloroethylene (TCE) and other chlorinated solvents. The technology demonstration was located at a seep from the K-1070-C/D Classified Burial Ground at the Oak Ridge K-25 Site. The technology demonstration was designed to evaluate the performance of two different types of cometabolic processes. In both cases, the TCE is cometabolized in the sense that utilization of a different primary substrate is necessary to obtain the simultaneous cometabolism of TCE. Trichloroethylene alone is unable to support growth and maintenance of the microorganisms. Methanotrophic (methane-utilizing) technology was demonstrated first; aromatic-utilizing microorganisms were demonstrated later. The demonstration was based on scaleup of laboratory and bench-scale prototype equipment that was used to establish the technical feasibility of the processes.This report documents the operation of the methanotrophic bioreactor system to treat the seep water at the demonstration site. The initial objectives were to demonstrate stable operation of the bioreactors and associated equipment, including the pretreatment and effluent polishing steps; and evaluate the biodegradation of TCE and other organics in the seep water for the three operating modes--air oxidation pretreatment, steam-stripping pretreatment, and no pretreatment.

  7. Site-specific earthquake response analysis for Paducah Gaseous Diffusion Plant, Paducah, Kentucky. Final report

    SciTech Connect

    Sykora, D.W.; Davis, J.J.

    1993-08-01

    The Paducah Gaseous Diffusion Plant (PGDP), owned by the US Department of Energy (DOE) and operated under contract by Martin Marietta Energy systems, Inc., is located southwest of Paducah, Kentucky. An aerial photograph and an oblique sketch of the plant are shown in Figures 1 and 2, respectively. The fenced portion of the plant consists of 748 acres. This plant was constructed in the 1950`s and is one of only two gaseous diffusion plants in operation in the United States; the other is located near Portsmouth, Ohio. The facilities at PGDP are currently being evaluated for safety in response to natural seismic hazards. Design and evaluation guidelines to evaluate the effects of earthquakes and other natural hazards on DOE facilities follow probabilistic hazard models that have been outlined by Kennedy et al. (1990). Criteria also established by Kennedy et al. (1990) classify diffusion plants as ``moderate hazard`` facilities. The US Army Engineer Waterways Experiment Station (WES) was tasked to calculate the site response using site-specific design earthquake records developed by others and the results of previous geotechnical investigations. In all, six earthquake records at three hazard levels and four individual and one average soil columns were used.

  8. Lower Columbia River and Estuary Ecosystem Restoration Program Reference Site Study: 2011 Restoration Analysis - FINAL REPORT

    SciTech Connect

    Borde, Amy B.; Cullinan, Valerie I.; Diefenderfer, Heida L.; Thom, Ronald M.; Kaufmann, Ronald M.; Zimmerman, Shon A.; Sagar, Jina; Buenau, Kate E.; Corbett, C.

    2012-05-31

    The Reference Site (RS) study is part of the research, monitoring, and evaluation (RME) effort developed by the Action Agencies (Bonneville Power Administration [BPA], U.S. Army Corps of Engineers, Portland District [USACE], and U.S. Bureau of Reclamation) in response to Federal Columbia River Power System (FCRPS) Biological Opinions (BiOp). While the RS study was initiated in 2007, data have been collected at relatively undisturbed reference wetland sites in the LCRE by PNNL and collaborators since 2005. These data on habitat structural metrics were previously summarized to provide baseline characterization of 51 wetlands throughout the estuarine and tidal freshwater portions of the 235-km LCRE; however, further analysis of these data has been limited. Therefore, in 2011, we conducted additional analyses of existing field data previously collected for the Columbia Estuary Ecosystem Restoration Program (CEERP) - including data collected by PNNL and others - to help inform the multi-agency restoration planning and ecosystem management work underway in the LCRE.

  9. Evaluation of in situ remedial technologies for sites contaminated with hydrocarbons. Final report

    SciTech Connect

    Lige, J.E.; Kunkel, M.L.; MacFarlane, I.D.

    1998-01-01

    This report presents the results of an extensive literature review that was performed to assess the overall effectiveness, applicability, and limitations of the various in situ technologies currently being applied to remediate sites contaminated by petroleum hydrocarbons. Of 17 technologies that were identified in an initial review and database search, nine were selected as widely used or promising for increased future use: soil vapor extraction, bioventing, pump and treat, aquifer air sparging, biosparging, in situ enhanced aquifer bioremediation, natural attenuation, in-well aeration, and dual-phase extraction. Following a general discussion of in situ technology, the report devotes one chapter to each of these nine technologies, presenting in each chapter a description of the technology; criteria to be used in considering applicability of the technology at a site; a discussion of design criteria and operating conditions; a strategy for monitoring remediation and determining when clean-up criteria are met; a discussion of performance-related issues; documented case studies; and a hypothetical application of the technology. Report appendices provide an overview of petroleum hydrocarbon constituents and their properties, and a glossary of terms.

  10. Participation in the Creede Scientific Drilling Project as on-site Principal Investigator. Final report

    SciTech Connect

    Hulen, J.B.

    1992-06-01

    Scientific questions addressed by the Creede Scientific Drilling Project were as follows (Bethke et al., 1992): (1) Did the lacustrine sedimentary sequence filling the moat of Creede caldera serve as reservoir for the moderately-saline aqueous fluids which scavenged and then transported silver and base metals to ore-depositional sites for the rich epithermal deposits of the Creede mining district (Fig. 1)?; (2) what were the chemical and isotopic compositions of these fluids prior to their entry into the Creede fracture (later vein) system; (3) how did these chemical and isotopic compositions evolve in transit to the ore-depositional site?; (4) how did the Creede caldera form and evolve?; (5) what is the present thermal regime in Creede caldera moat? {hor_ellipsis}the, paleothermal regime?; (5) what are the hydrologic transport properties of the moat sedimentary rocks?; (6) what diagenetic or hydrothermal veins disrupt the moat sedimentary sequence, and what do their paragenetic relationships, mineralogic compositions, fluid-inclusion characteristics, and stable-isotope systematics reveal about evolution of the Creede hydrothermal system? Two Creede caldera moat drill holes were completed for this project.

  11. A NMR and MD study of the active site of factor Xa by selective inhibitors

    NASA Astrophysics Data System (ADS)

    Doan, B. T.; Fraternali, F.; Do, Q. T.; Atkinson, R. A.; Palmas, P.; Sklenar, V.; Wildgoose, P.; Strop, P.; Saudek, V.

    1998-02-01

    The structure of two selective inhibitors obtained by the screening of a vast combinatorial library, Ac-Tyr-Ile-Arg-Ile-NH2 and Ac-(4-amino-Phe)-(Cyc.-Gly)-NH2, in the active site of the blood clotting enzyme factor Xa was determined using transferred NOE NMR and simulated annealing (SA) under NMR constraints. The refined structures of the inhibitors were docked in the active site and SA was performed inside the enzyme which has been kept as a rigid charged template. The final structures were optimised by molecular dynamics simulation of the complexes in water. The inhibitors assume a compact, very well defined conformation embedded in the binding site without blocking the catalysis. The model allows to explain the mode of action, affinity and specificity. L'étude structurale d'inhibiteurs du facteur Xa, une enzyme de coagulation, obtenus par chimie combinatoire : Ac-Tyr-Ile-Arg-Ile-NH2, Ac-(4-amino-Phe)-(Cyc.-Gly)-NH2, a été réalisée par RMN NOE de transfert et modélisation moléculaire. Les structures ont été calculées sous contraintes RMN : géométrie de distance, recuit simulé et minimisation, affinées par une recherche conformationnelle et recuit de l'inhibiteur placé dans le site actif et optimisées par simulation de dynamique moléculaire du complexe dans l'eau. L'inhibiteur présente une structure compacte positionnée dans le site d'interaction hors d'accès du site catalytique. Ce modèle permet d'expliquer le mode d'action, l'affinité et la spécificité des peptides.

  12. Aromatase is expressed and active in the rainbow trout oocyte during final oocyte maturation.

    PubMed

    Gohin, Maella; Bodinier, Pascal; Fostier, Alexis; Chesnel, Franck; Bobe, Julien

    2011-07-01

    While it is generally well accepted that the ovarian follicular sites of estradiol-17β (E2) synthesis are restricted to somatic cells, the possible contribution of the germinal compartment has received little or no attention in teleosts. In order to demonstrate the expression of ovarian aromatase in the oocyte, cyp19a1a mRNA was studied in ovarian follicles by in situ hybridization. In addition, the expression of cyp19a1a was studied in both somatic and germinal compartments of the ovarian follicle in rainbow trout (Oncorhynchus mykiss) during final oocyte maturation (i.e., maturational competence acquisition and subsequent meiosis resumption) by real-time PCR. The enzymatic activity of ovarian aromatase was also studied in both somatic and germinal compartments of the ovarian follicle. Finally, E2 levels were monitored in follicle-enclosed oocytes throughout the pre-ovulatory period. We were able to demonstrate a significant ovarian aromatase expression and activity in the late vitellogenic oocyte. Furthermore, a dramatic decrease in aromatase expression and activity occurs in the oocyte during late oogenesis, concomitantly with the trend observed in surrounding follicular layers. We also report an unexpected increase of E2 levels in the oocyte during the pre-ovulatory period. To our knowledge, these observations are reported for the first time in any teleost species. Together, our data support the hypothesis of the participation of the germinal compartment in follicular estrogen synthesis and a biological role of E2 during oocyte and/or early embryo development.

  13. Barometric pressure transient testing applications at the Nevada Test Site. Nuclear chimney analysis. Final report

    SciTech Connect

    Hanson, J.M.

    1985-12-01

    Investigations of barometric pressure testing of NTS nuclear chimneys were reviewed. This review includes the models used in the interpretation, methods of analysis, and results. Analytic and semi-analytic models were presented and applied to both historical data and new data taken for this current project. An interpretation technique based on non-linear least squares methods was used to analyze this data in terms of historic and more recent chimney models. Finally, a detailed discussion of radioactive gas transport due to surface barometric pressure fluctuations was presented. This mechanism of transport, referred to as ''barometric pumping,'' is presented in terms of conditions likely to be encountered at the NTS. The report concludes with a discussion of the current understanding of gas flow properties in the alluvial and volcanic areas of the NTS, and suggestions for future efforts directed toward increasing this understanding are presented.

  14. Active gelatinase B is identified by histozymography in the cartilage resorption sites of developing long bones.

    PubMed

    Lee, E R; Murphy, G; El-Alfy, M; Davoli, M A; Lamplugh, L; Docherty, A J; Leblond, C P

    1999-07-01

    In order to determine which proteinases mediate the resorption of endochondral cartilage in the course of long bone development, a novel assay called "histozymography" has been developed. In this assay, frozen sections of tibial head from 21-day-old rats are placed for 4 hr at room temperature on light-exposed photographic emulsion (composed of silver grains embedded in gelatin). We report a localized but complete digestion of emulsion gelatin facing two tissue sites which are, therefore, presumed to contain an active proteinase. One of the sites is localized at the growth plate surface forming the epiphysis/metaphysis interface. The other consists of small patches located within the epiphysis at the edge of the marrow space. Both sites are engaged in the resorption of endochondral cartilage. In both sites, inhibitor tests have established that the involved proteinase is a gelatinase. Furthermore, the use of neutralizing antibodies against gelatinase A or B have demonstrated that only those that are specific for the latter block the reaction. That gelatinase B is present in the two sites has been confirmed by light microscopic immunohistochemistry. Finally, when immunoelectron microscopy is used for fine localization of the cartilage structures that form the epiphysis/metaphysis interface, the enzyme is detected within the 0.5-microm thick edge of the cartilage, and outside the cartilage, it is present in debris composed of type II collagen-rich fibrils in various states of digestion. It is concluded that gelatinase B attacks the edge of an endochondral cartilage and helps to solubilize the type II-collagen-rich fibrillar framework, which is then released as debris for further digestion. This final step opens the way to invasion by capillaries, thereby making possible the replacement of cartilage by bone. Dev Dyn 1999;215:190-205.

  15. Preliminary access routes and cost study analyses for seven potentially acceptable salt sites: Final report, October 1984

    SciTech Connect

    Not Available

    1987-02-01

    This report analyzes highway and railroad access to seven potentially acceptable salt repository sites: Richton Dome and Cypress Creek Dome in Mississippi, Vacherie Dome in Louisiana, Swisher County and Deaf Smith County in Texas, and Davis Canyon and Lavender Canyon in utah. The objectives of the study were to investigate the routing of reasonable access corridors to the sites, describe major characteristics of each route, and estimate the costs for constructing or upgrading highways and railroads. The routes used in the analysis are not necessarily recommended or preferred over other routes, nor do they represent an implied final selection. Detailed engineering studies must be performed for the Davis Canyon and Lavender Canyon highway access before the analyzed routes can be considered to be viable. 20 refs., 7 figs., 3 tabs.

  16. Superfund Record of Decision (EPA Region 1): PSC Resources Site, Palmer, MA. (First remedial action), September 1992. Final report

    SciTech Connect

    Not Available

    1992-09-15

    The 21.5-acre PSC Resources site is a former waste oil and solvent reclamation facility located in Palmer, Hampden County, Massachusetts. Since 1898, there have been several owners of the PSC property, most involved in oil industry functions. In 1974, PSC Resources, Inc., purchased the property to operate an oil storage and processing facility, and in 1976, the company name was changed to Ag-Met Oil Services, Inc. The company began accepting solvents and lacquers for collection and disposal. The ROD addresses the final remedy for the site, which includes both source control and management of migration components. The primary contaminants of concern affecting the soil, sediment, debris, ground water, and surface water are VOCs, including benzene, PCE, and TCE; other organics, including PAHs and PCBs; and metals, including arsenic and lead.

  17. Hydraulic Testing of Salado Formation Evaporites at the Waste Isolation Pilot Plant Site: Final Report

    SciTech Connect

    Beauheim, Richard L.; Domski, Paul S.; Roberts, Randall M.

    1999-07-01

    This report presents interpretations of hydraulic tests conducted in bedded evaporates of the Salado Formation from May 1992 through May 1995 at the Waste Isolation Pilot Plant (WIPP) site in southeastern New Mexico. The WIPP is a US Department of Energy research and development facility designed to demonstrate safe disposal of transuranic wastes from the nation's defense programs. The WIPP disposal horizon is located in the lower portion of the Permian Salado Formation. The hydraulic tests discussed in this report were performed in the WIPP underground facility by INTERA inc. (now Duke Engineering and Services, Inc.), Austin, Texas, following the Field Operations Plan and Addendum prepared by Saulnier (1988, 1991 ) under the technical direction of Sandia National Laboratories, Albuquerque, New Mexico.

  18. Environmentally based siting assessment for synthetic-liquid-fuels facilities. Final report

    SciTech Connect

    1980-01-01

    A detailed assessment of the major environmental constraints to siting a synthetic fuels industry and the results of that assessment are used to determine on a regional basis the potential for development of such an industry with minimal environmental conflicts. Secondly, the ability to mitigate some of the constraining impacts through alternative institutional arrangements, especially in areas that are judged to have a low development potential is also assessed. Limitations of the study are delineated, but specifically, the study is limited geographically to well-defined boundaries that include the prime coal and oil shale resource areas. The critical factors used in developing the framework are air quality, water availability, socioeconomic capacity, ecological sensitivity, environmental health, and the management of Federally owned lands. (MCW)

  19. Maryland power plant siting program radioecology database management system: format for coding radioecology data. Final report

    SciTech Connect

    Domotor, S.L.

    1986-01-01

    The Radioecology Laboratory of the State of Maryland Power Plant Siting Program (PPSP) conducts routine radiological monitoring programs designed to assess the environmental impact of radionuclides released by nuclear power plants affecting Maryland. The PPSP radioecology database management system was initiated to store existing and future monitoring data collected by PPSP and its subcontractors in a computer file format. From these files, SAS (Statistical Analysis System) datasets are created for qualitative and quantitative analysis of monitoring data, for modeling studies through incorporation of this data, or for predicting environmental impact. The system was designed to accommodate both gamma and beta radionuclide analyses from water, sediment, soil, air, foodstuff, and aquatic and terrestrial flora and fauna sample types. Plant releases of radionuclides and physical and chemical environmental parameters can also be stored.

  20. Active Site Loop Conformation Regulates Promiscuous Activity in a Lactonase from Geobacillus kaustophilus HTA426

    PubMed Central

    Zhang, Yu; An, Jiao; Yang, Guang-Yu; Bai, Aixi; Zheng, Baisong; Lou, Zhiyong; Wu, Geng; Ye, Wei; Chen, Hai-Feng; Feng, Yan; Manco, Giuseppe

    2015-01-01

    Enzyme promiscuity is a prerequisite for fast divergent evolution of biocatalysts. A phosphotriesterase-like lactonase (PLL) from Geobacillus kaustophilus HTA426 (GkaP) exhibits main lactonase and promiscuous phosphotriesterase activities. To understand its catalytic and evolutionary mechanisms, we investigated a “hot spot” in the active site by saturation mutagenesis as well as X-ray crystallographic analyses. We found that position 99 in the active site was involved in substrate discrimination. One mutant, Y99L, exhibited 11-fold improvement over wild-type in reactivity (kcat/Km) toward the phosphotriesterase substrate ethyl-paraoxon, but showed 15-fold decrease toward the lactonase substrate δ-decanolactone, resulting in a 157-fold inversion of the substrate specificity. Structural analysis of Y99L revealed that the mutation causes a ∼6.6 Å outward shift of adjacent loop 7, which may cause increased flexibility of the active site and facilitate accommodation and/or catalysis of organophosphate substrate. This study provides for the PLL family an example of how the evolutionary route from promiscuity to specificity can derive from very few mutations, which promotes alteration in the conformational adjustment of the active site loops, in turn draws the capacity of substrate binding and activity. PMID:25706379

  1. Characterization of the active site of ADP-ribosyl cyclase.

    PubMed

    Munshi, C; Thiel, D J; Mathews, I I; Aarhus, R; Walseth, T F; Lee, H C

    1999-10-22

    ADP-ribosyl cyclase synthesizes two Ca(2+) messengers by cyclizing NAD to produce cyclic ADP-ribose and exchanging nicotinic acid with the nicotinamide group of NADP to produce nicotinic acid adenine dinucleotide phosphate. Recombinant Aplysia cyclase was expressed in yeast and co-crystallized with a substrate, nicotinamide. x-ray crystallography showed that the nicotinamide was bound in a pocket formed in part by a conserved segment and was near the central cleft of the cyclase. Glu(98), Asn(107) and Trp(140) were within 3.5 A of the bound nicotinamide and appeared to coordinate it. Substituting Glu(98) with either Gln, Gly, Leu, or Asn reduced the cyclase activity by 16-222-fold, depending on the substitution. The mutant N107G exhibited only a 2-fold decrease in activity, while the activity of W140G was essentially eliminated. The base exchange activity of all mutants followed a similar pattern of reduction, suggesting that both reactions occur at the same active site. In addition to NAD, the wild-type cyclase also cyclizes nicotinamide guanine dinucleotide to cyclic GDP-ribose. All mutant enzymes had at least half of the GDP-ribosyl cyclase activity of the wild type, some even 2-3-fold higher, indicating that the three coordinating amino acids are responsible for positioning of the substrate but not absolutely critical for catalysis. To search for the catalytic residues, other amino acids in the binding pocket were mutagenized. E179G was totally devoid of GDP-ribosyl cyclase activity, and both its ADP-ribosyl cyclase and the base exchange activities were reduced by 10,000- and 18,000-fold, respectively. Substituting Glu(179) with either Asn, Leu, Asp, or Gln produced similar inactive enzymes, and so was the conversion of Trp(77) to Gly. However, both E179G and the double mutant E179G/W77G retained NAD-binding ability as shown by photoaffinity labeling with [(32)P]8-azido-NAD. These results indicate that both Glu(179) and Trp(77) are crucial for catalysis and

  2. Active system area networks for data intensive computations. Final report

    SciTech Connect

    2002-04-01

    The goal of the Active System Area Networks (ASAN) project is to develop hardware and software technologies for the implementation of active system area networks (ASANs). The use of the term ''active'' refers to the ability of the network interfaces to perform application-specific as well as system level computations in addition to their traditional role of data transfer. This project adopts the view that the network infrastructure should be an active computational entity capable of supporting certain classes of computations that would otherwise be performed on the host CPUs. The result is a unique network-wide programming model where computations are dynamically placed within the host CPUs or the NIs depending upon the quality of service demands and network/CPU resource availability. The projects seeks to demonstrate that such an approach is a better match for data intensive network-based applications and that the advent of low-cost powerful embedded processors and configurable hardware makes such an approach economically viable and desirable.

  3. Mutations inducing an active-site aperture in Rhizobium sp. sucrose isomerase confer hydrolytic activity.

    PubMed

    Lipski, Alexandra; Watzlawick, Hildegard; Ravaud, Stéphanie; Robert, Xavier; Rhimi, Moez; Haser, Richard; Mattes, Ralf; Aghajari, Nushin

    2013-02-01

    Sucrose isomerase is an enzyme that catalyzes the production of sucrose isomers of high biotechnological and pharmaceutical interest. Owing to the complexity of the chemical synthesis of these isomers, isomaltulose and trehalulose, enzymatic conversion remains the preferred method for obtaining these products. Depending on the microbial source, the ratio of the sucrose-isomer products varies significantly. In studies aimed at understanding and explaining the underlying molecular mechanisms of these reactions, mutations obtained using a random-mutagenesis approach displayed a major hydrolytic activity. Two of these variants, R284C and F164L, of sucrose isomerase from Rhizobium sp. were therefore crystallized and their crystal structures were determined. The three-dimensional structures of these mutants allowed the identification of the molecular determinants that favour hydrolytic activity compared with transferase activity. Substantial conformational changes resulting in an active-site opening were observed, as were changes in the pattern of water molecules bordering the active-site region.

  4. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Durango, Colorado: Remedial action selection report. Revised final report

    SciTech Connect

    Not Available

    1991-12-01

    The uranium mill tailings site near Durango, Colorado, was one of 24 inactive uranium mill sites designated to be remediated by the US Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). Part of the UMTRCA requires that the US Nuclear Regulatory Commission (NRC) concur with the DOE`s Remedial Action Plan (RAP) and certify that the remedial action conducted at the site complies with the standards promulgated by the US Environmental Protection Agency (EPA). Included in the RAP is this Remedial Action Selection Report (RAS), which has been developed to serve a two-fold purpose. First, it describes the activities that have been conducted by the DOE to accomplish remediation and long-term stabilization and control of the radioactive materials at the inactive uranium mill processing site near Durango, Colorado. Secondly, this document and the rest of the RAP, upon concurrence and execution by the DOE, the State of Colorado, and the NRC, become Appendix B of the Cooperative Agreement between the DOE and the State of Colorado.

  5. Remedial action plan and site design for stabilization of the inactive uranium processing site at Naturita, Colorado. Remedial action selection report, Attachment 2, Geology report: Preliminary final

    SciTech Connect

    Not Available

    1993-08-01

    The uranium processing site near Naturita, Colorado, is one of 24 inactive uranium mill sites designated to be cleaned up by the US Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA), Public Law 95-604. Part of the UMTRCA requires that the US Nuclear Regulatory Commission (NRC) concur with the DOE`s remedial action plan (RAP) and certify that the remedial action conducted at the site complies with the standards promulgated by the US Environmental Protection Agency (EPA). Included in the RAP is this Remedial Action Selection Report (RAS), which serves two purposes. First, it describes the activities that are proposed by the DOE to accomplish remediation and long-term stabilization and control of the radioactive materials at the inactive uranium processing site near Naturita, Colorado. Second, this document and the rest of the RAP, upon concurrence and execution by the DOE, the state of Colorado, and the NRC, become Appendix B of the cooperative agreement between the DOE and the State of Colorado.

  6. Analysis of Hydrogen Tunneling in an Enzyme Active Site using von Neumann Measurements

    PubMed Central

    Sumner, Isaiah; Iyengar, Srinivasan S.

    2010-01-01

    We build on our earlier quantum wavepacket study of hydrogen transfer in the biological enzyme, soybean lipoxygenase-1, by using von Neumann quantum measurement theory to gain qualitative insights into the transfer event. We treat the enzyme active site as a measurement device which acts on the tunneling hydrogen nucleus via the potential it exerts at each configuration. A series of changing active site geometries during the tunneling process effects a sequential projection of the initial, reactant state onto the final, product state. We study this process using several different kinds of von Neumann measurements and show how a discrete sequence of such measurements not only progressively increases the projection of the hydrogen nuclear wavepacket onto the product side but also favors proton over deuteron transfer. Several qualitative features of the hydrogen tunneling problem found in wavepacket dynamics studies are also recovered here. These include the shift in the “transition state” towards the reactant as a result of nuclear quantization, greater participation of excited states in the case of deuterium, and presence of critical points along the reaction coordinate that facilitate hydrogen and deuterium transfer and coincide with surface crossings. To further “tailor” the dynamics, we construct a perturbation to the sequence of measurements, that is a perturbation to the dynamical sequence of active site geometry evolution, which leads us to insight on the existence of sensitive regions of the reaction profile where subtle changes to the dynamics of the active site can have an effect on the hydrogen and deuterium transfer process. PMID:22933858

  7. Phase I decontamination of the J. C. Haynes site, Newark, Ohio. Final report

    SciTech Connect

    Emswiler, T R

    1985-11-01

    Phase I consisted of the primary decontamination, packaging, and shipment of all /sup 241/Am-contaminated gloveboxes, vent system, and miscellaneous waste items located in the laboratory restricted area in the J.C. Haynes house. The primary goals of Phase I were to locate and account for a major quantity of /sup 241/Am which was unaccounted for and to remove all radioactive materials and contamination posing an imminent hazard to public health and safety. All Phase I operations were conducted under a Quality Assurance (QA) Program Plan and QA procedures written specifically for this program. In addition, certain generic Battelle QA procedures were used for routine tasks. All operations were conducted under strict health physics supervision and procedures. Cognizant ORAU and US Nuclear Regulatory Commission (NRC) personnel were on site during the entire Phase I operation and provided support and approval in the daily operations. All staff members had participated in previous decontamination and decommissioning programs involving transuranic waste and completed Phase I in a well controlled, timely, and safe manner.

  8. Alternate hybrid power sources for remote site applications. Final report, February 1980-February 1981

    SciTech Connect

    Powell, W.R.; Taylor, R.J.; Baron, J.L.; Mengel, E.E.; Ray, J.C.

    1981-02-01

    Unmanned Coast Guard lighthouses currently dependent on diesel generators are classified into six climatic groups and three power classes for generic analysis. Methods for describing both the hourly average and statistical characteristics of the solar energy and wind power available in each of these six climatic regions are developed. The technology currently available or expected during the next five years for collecting energy from the environment and storing it for subsequent generation of electric power is reviewed. A method for computing battery life as a function of the hourly use pattern is developed . A life-cycle-cost analysis methodology applicable to continuously variable life expectancies is developed and illustrated. Diesel generator costs, including service visit expense, are modeled. Other factors relating to the analysis of alternate energy systems as supplements to diesel-electric generators at remote sites are discussed. Simulations show that the use of storage batteries and a DC to AC inverter permits the diesel to be off during periods of low power demand with significant reduction in both annual fuel use and cost. Supplementing this basic diesel-battery hybrid with energy collected from the environment is cost effective and saves additional fuel. Other hourly simulation model results are given and generic systems are recommended for construction and test.

  9. High resolution seismic survey, Pen Branch Fault, Savannah River Site, South Carolina. Final report

    SciTech Connect

    Berkman, E.

    1991-04-01

    An investigation of the Pen Branch Fault at the Savannah River Site by a series of short, high resolution seismic reflection lines was conducted. The purpose was to acquire, process, and interpret 19.9 miles of data, optimized for the upper 300 ft of geologic strata, in sufficient density such that processing performed in the conventional stepwise approach, followed by detailed interpretation, would define small scale spatial variability and structural features in the vicinity of the fault leading to definition of the location of the fault, the shallowest extent of the fault, and the quantification of the sense and magnitude of motion. The depth of optimization for the last two lines was modified to the 300 ft of geologic strata immediately above basement. Three older seismic surveys, other geophysical data, and associated borehole and geologic data were reviewed. The equipment and the acquisition, processing, and interpretation procedures are discussed in the report. The report includes a detailed line by line description and discussion of the interpretation. Figures include reference maps, contour displays of the stacking and interval velocities, diagrammatic references sketches of the interpreted layering and sedimentary features, index sketches, and specific color prints made on the workstation during the course of the interpretation. A volume of manuals on seismic devices and related equipment is included.

  10. Surface and subsurface cleanup protocol for radionuclides, Gunnison, Colorado, UMTRA project processing site. Final [report

    SciTech Connect

    Not Available

    1993-09-01

    Surface and subsurface soil cleanup protocols for the Gunnison, Colorado, processing sits are summarized as follows: In accordance with EPA-promulgated land cleanup standards (40 CFR 192), in situ Ra-226 is to be cleaned up based on bulk concentrations not exceeding 5 and 15 pCi/g in 15-cm surface and subsurface depth increments, averaged over 100-m{sup 2} grid blocks, where the parent Ra-226 concentrations are greater than, or in secular equilibrium with, the Th-230 parent. A bulk interpretation of these EPA standards has been accepted by the Nuclear Regulatory Commission (NRC), and while the concentration of the finer-sized soil fraction less than a No. 4 mesh sieve contains the higher concentration of radioactivity, the bulk approach in effect integrates the total sample radioactivity over the entire sample mass. In locations where Th-230 has differentially migrated in subsoil relative to Ra-226, a Th-230 cleanup protocol has been developed in accordance with Supplemental Standard provisions of 40 CFR 192 for NRC/Colorado Department of Health (CDH) approval for timely implementation. Detailed elements of the protocol are contained in Appendix A, Generic Protocol from Thorium-230 Cleanup/Verification at UMTRA Project Processing Sites. The cleanup of other radionuclides or nonradiological hazards that pose a significant threat to the public and the environment will be determined and implemented in accordance with pathway analysis to assess impacts and the implications of ALARA specified in 40 CFR 192 relative to supplemental standards.

  11. Savannah River Site Spent Nuclear Fuel Management Final Environmental Impact Statement

    SciTech Connect

    N /A

    2000-04-14

    The proposed DOE action considered in this environmental impact statement (EIS) is to implement appropriate processes for the safe and efficient management of spent nuclear fuel and targets at the Savannah River Site (SRS) in Aiken County, South Carolina, including placing these materials in forms suitable for ultimate disposition. Options to treat, package, and store this material are discussed. The material included in this EIS consists of approximately 68 metric tons heavy metal (MTHM) of spent nuclear fuel 20 MTHM of aluminum-based spent nuclear fuel at SRS, as much as 28 MTHM of aluminum-clad spent nuclear fuel from foreign and domestic research reactors to be shipped to SRS through 2035, and 20 MTHM of stainless-steel or zirconium-clad spent nuclear fuel and some Americium/Curium Targets stored at SRS. Alternatives considered in this EIS encompass a range of new packaging, new processing, and conventional processing technologies, as well as the No Action Alternative. A preferred alternative is identified in which DOE would prepare about 97% by volume (about 60% by mass) of the aluminum-based fuel for disposition using a melt and dilute treatment process. The remaining 3% by volume (about 40% by mass) would be managed using chemical separation. Impacts are assessed primarily in the areas of water resources, air resources, public and worker health, waste management, socioeconomic, and cumulative impacts.

  12. Crystal Structure of Albaflavenone Monooxygenase Containing a Moonlighting Terpene Synthase Active Site*

    PubMed Central

    Zhao, Bin; Lei, Li; Vassylyev, Dmitry G.; Lin, Xin; Cane, David E.; Kelly, Steven L.; Yuan, Hang; Lamb, David C.; Waterman, Michael R.

    2009-01-01

    Albaflavenone synthase (CYP170A1) is a monooxygenase catalyzing the final two steps in the biosynthesis of this antibiotic in the soil bacterium, Streptomyces coelicolor A3(2). Interestingly, CYP170A1 shows no stereo selection forming equal amounts of two albaflavenol epimers, each of which is oxidized in turn to albaflavenone. To explore the structural basis of the reaction mechanism, we have studied the crystal structures of both ligand-free CYP170A1 (2.6 Å) and complex of endogenous substrate (epi-isozizaene) with CYP170A1 (3.3 Å). The structure of the complex suggests that the proximal epi-isozizaene molecules may bind to the heme iron in two orientations. In addition, much to our surprise, we have found that albaflavenone synthase also has a second, completely distinct catalytic activity corresponding to the synthesis of farnesene isomers from farnesyl diphosphate. Within the cytochrome P450 α-helical domain both the primary sequence and x-ray structure indicate the presence of a novel terpene synthase active site that is moonlighting on the P450 structure. This includes signature sequences for divalent cation binding and an α-helical barrel. This barrel is unusual because it consists of only four helices rather than six found in all other terpene synthases. Mutagenesis establishes that this barrel is essential for the terpene synthase activity of CYP170A1 but not for the monooxygenase activity. This is the first bifunctional P450 discovered to have another active site moonlighting on it and the first time a terpene synthase active site is found moonlighting on another protein. PMID:19858213

  13. Site-specific PEGylation of lidamycin and its antitumor activity

    PubMed Central

    Li, Liang; Shang, Boyang; Hu, Lei; Shao, Rongguang; Zhen, Yongsu

    2015-01-01

    In this study, N-terminal site-specific mono-PEGylation of the recombinant lidamycin apoprotein (rLDP) of lidamycin (LDM) was prepared using a polyethyleneglycol (PEG) derivative (Mw 20 kDa) through a reactive terminal aldehyde group under weak acidic conditions (pH 5.5). The biochemical properties of mPEG-rLDP-AE, an enediyne-integrated conjugate, were analyzed by SDS-PAGE, RP-HPLC, SEC-HPLC and MALDI-TOF. Meanwhile, in vitro and in vivo antitumor activity of mPEG-rLDP-AE was evaluated by MTT assays and in xenograft model. The results indicated that mPEG-rLDP-AE showed significant antitumor activity both in vitro and in vivo. After PEGylation, mPEG-rLDP still retained the binding capability to the enediyne AE and presented the physicochemical characteristics similar to that of native LDP. It is of interest that the PEGylation did not diminish the antitumor efficacy of LDM, implying the possibility that this derivative may function as a payload to deliver novel tumor-targeted drugs. PMID:26579455

  14. Active Transport of Nanomaterials Using Motor Proteins -Final Report

    SciTech Connect

    Hess, Henry

    2005-09-01

    During the six months of funding we have focused first on the completion of the research begun at the University of Washington in the previous funding cycle. Specifically, we developed a method to polymerize oriented networks of microtubules on lithographically patterned surfaces (M.S. thesis Robert Doot). The properties of active transport have been studied detail, yielding insights into the dispersion mechanisms (Nitta et al.). The assembly of multifunctional structures with a microtubule core has been investigated (Ramachandran et al.). Isaac Luria (B.S. in physics, U. of Florida 2005) worked on the directed assembly of nanoscale, non-equilibrium structures as a summer intern. He is now a graduate student in my group at the University of Florida. T. Nitta and H. Hess: Dispersion in Active Transport by Kinesin-Powered Molecular Shuttles, Nano Letters, 5, 1337-1342 (2005) S. Ramachandran, K.-H. Ernst, G. D. Bachand, V. Vogel, H. Hess*: Selective Loading of Kinesin-Powered Molecular Shuttles with Protein Cargo and its Application to Biosensing, submitted to Small (2005)

  15. Allosteric site-mediated active site inhibition of PBP2a using Quercetin 3-O-rutinoside and its combination.

    PubMed

    Rani, Nidhi; Vijayakumar, Saravanan; P T V, Lakshmi; Arunachalam, Annamalai

    2016-08-01

    Recent crystallographic study revealed the involvement of allosteric site in active site inhibition of penicillin binding protein (PBP2a), where one molecule of Ceftaroline (Cef) binds to the allosteric site of PBP2a and paved way for the other molecule (Cef) to bind at the active site. Though Cef has the potency to inhibit the PBP2a, its adverse side effects are of major concern. Previous studies have reported the antibacterial property of Quercetin derivatives, a group of natural compounds. Hence, the present study aims to evaluate the effect of Quercetin 3-o-rutinoside (Rut) in allosteric site-mediated active site inhibition of PBP2a. The molecular docking studies between allosteric site and ligands (Rut, Que, and Cef) revealed a better binding efficiency (G-score) of Rut (-7.790318) and Cef (-6.194946) with respect to Que (-5.079284). Molecular dynamic (MD) simulation studies showed significant changes at the active site in the presence of ligands (Rut and Cef) at allosteric site. Four different combinations of Rut and Cef were docked and their G-scores ranged between -6.320 and -8.623. MD studies revealed the stability of the key residue (Ser403) with Rut being at both sites, compared to other complexes. Morphological analysis through electron microscopy confirmed that combination of Rut and Cefixime was able to disturb the bacterial cell membrane in a similar fashion to that of Rut and Cefixime alone. The results of this study indicate that the affinity of Rut at both sites were equally good, with further validations Rut could be considered as an alternative for inhibiting MRSA growth.

  16. Site specific endonucleases for human genome mapping. Final report, April 1, 1992--March 31, 1994

    SciTech Connect

    Knoche, K.; Selman, S.; Hung, L.

    1994-06-01

    Current large scale genome mapping methodology suffers from a lack of tools for generating specific DNA fragments in the megabase size range. While technology such as pulsed field gel electrophoresis can resolve DNA fragments greater than 10 megabases in size, current methods for cleaving mammalian DNA using bacterial restriction enzymes are incapable of producing such fragments. Though several multidimensional approaches are underway to overcome this limitation, there currently is no single step procedure to generate specific DNA fragments in the 2-100 megabase size range. In order to overcome these limitations, we proposed to develop a family of site-specific endonucleases capable of generating DNA fragments in the 2-100 megabase size range in a single step. Additionally, we proposed to accomplish this by relaxing the specificity of a very-rare cutting intron-encoded endonucleases, I-Ppo I, and potentially using the process as a model for development of other enzymes. Our research has uncovered a great deal of information about intron-encoded endonucleases. We have found that I-Ppo I has a remarkable ability to tolerate degeneracy within its recognition sequence, and we have shown that the recognition sequence is larger than 15 base pairs. These findings suggest that a detailed study of the mechanism by which intron-encoded endonucleases recognize their target sequences should provide new sights into DNA-protein interactions; this had led to a continuation of the study of I-Ppo I in Dr. Raines` laboratory and we expect a more detailed understanding of the mechanism of I-Ppo I action to result.

  17. Energy conserving site design: Greenbrier case study, Chesapeake, Virginia. Final report

    SciTech Connect

    Not Available

    1980-04-01

    A specific case study of project planning for energy conservation for a major planned unit development at the 3000-acre Greenbrier development site in Chesapeake, Virginia, is summarized. The research suggests that very considerable reductions in energy conservation can be achieved within the confines of private-sector land development and residential construction with increased incremental costs of $200.00 to $3150.00 per dwelling unit. It is hypothesized that energy consumption at Greenbrier can be reduced by one-half with an average annual savings of 21,275 kWh per residential unit, using state-of-the-art technology with careful planning and control. This represents an annual savings $750.00 per unit at the current utility rate of 3.5 cents per kWh. These savings can be achieved through reduction in heating and cooling loads and application of more-efficient heating and cooling of the remaining loads. The reduction in loads are achieved by redesign of the land plan to include a higher percentage of south-facing lots, use of vegetation to modify microclimate, decreases in air infiltration, the use of 2 x 6 framing, better insulation, and the use of an insulated slab-on-grade foundation. Further energy savings can be expected by increased efficiencies in mechanical systems used for space heating and cooling and domestic hot water. When applied to the single-family portion of Greenbrier, containing 541 dwelling units, these options reduce the total end-use energy consumption 54.7%. This reduction represents an annual savings of $432,800.00 for an initial capital investment of $1.7 million.

  18. Superfund Record of Decision (EPA Region 3): Leetown Pesticide Site, Jefferson County, West Virginia, March 1986. Final report

    SciTech Connect

    Not Available

    1986-03-31

    The Leetown Pesticide site is located in northeast West Virginia, approximately 8 miles south of Martinsburg, West Virginia. The site is actually composed of a number of areas affected by surface disposal of pesticides, agricultural use of pesticides, and landfilling. A total of eight specific areas of waste disposal or accumulation were identified during the initial RI study. Of these eight areas, two were the result of alleged disposal of pesticide-contaminated debris from a fire that occurred in 1975 at the Miller Chemical Company. These two areas include the former pesticide pile and the suspected pesticide landfarm areas. Four of the contaminated areas are associated with former use of the land for orchard production. The two remaining sites are active landfills.

  19. Extensive site-directed mutagenesis reveals interconnected functional units in the alkaline phosphatase active site

    PubMed Central

    Sunden, Fanny; Peck, Ariana; Salzman, Julia; Ressl, Susanne; Herschlag, Daniel

    2015-01-01

    Enzymes enable life by accelerating reaction rates to biological timescales. Conventional studies have focused on identifying the residues that have a direct involvement in an enzymatic reaction, but these so-called ‘catalytic residues’ are embedded in extensive interaction networks. Although fundamental to our understanding of enzyme function, evolution, and engineering, the properties of these networks have yet to be quantitatively and systematically explored. We dissected an interaction network of five residues in the active site of Escherichia coli alkaline phosphatase. Analysis of the complex catalytic interdependence of specific residues identified three energetically independent but structurally interconnected functional units with distinct modes of cooperativity. From an evolutionary perspective, this network is orders of magnitude more probable to arise than a fully cooperative network. From a functional perspective, new catalytic insights emerge. Further, such comprehensive energetic characterization will be necessary to benchmark the algorithms required to rationally engineer highly efficient enzymes. DOI: http://dx.doi.org/10.7554/eLife.06181.001 PMID:25902402

  20. Molecular mimicry of substrate oxygen atoms by water molecules in the beta-amylase active site.

    PubMed

    Pujadas, G; Palau, J

    2001-08-01

    Soybean beta-amylase (EC 3.2.1.2) has been crystallized both free and complexed with a variety of ligands. Four water molecules in the free-enzyme catalytic cleft form a multihydrogen-bond network with eight strategic residues involved in enzyme-ligand hydrogen bonds. We show here that the positions of these four water molecules are coincident with the positions of four potential oxygen atoms of the ligands within the complex. Some of these waters are displaced from the active site when the ligands bind to the enzyme. How many are displaced depends on the shape of the ligand. This means that when one of the four positions is not occupied by a ligand oxygen atom, the corresponding water remains. We studied the functional/structural role of these four waters and conclude that their presence means that the conformation of the eight side chains is fixed in all situations (free or complexed enzyme) and preserved from unwanted or forbidden conformational changes that could hamper the catalytic mechanism. The water structure at the active pocket of beta-amylase is therefore essential for providing the ligand recognition process with plasticity. It does not affect the protein active-site geometry and preserves the overall hydrogen-bonding network, irrespective of which ligand is bound to the enzyme. We also investigated whether other enzymes showed a similar role for water. Finally, we discuss the potential use of these results for predicting whether water molecules can mimic ligand atoms in the active center.

  1. A split active site couples cap recognition by Dcp2 to activation

    PubMed Central

    Floor, Stephen N.; Jones, Brittnee N.; Hernandez, Gail A.; Gross, John D.

    2010-01-01

    Decapping by Dcp2 is an essential step in 5′-3′ mRNA decay. In yeast, decapping requires an open-to-closed transition in Dcp2, though the link between closure and catalysis remains elusive. Here we show using NMR that cap binds conserved residues on both the catalytic and regulatory domains of Dcp2. Lesions in the cap-binding site on the regulatory domain reduce the catalytic step two orders of magnitude and block formation of the closed state whereas Dcp1 enhances the catalytic step by a factor of ten and promotes closure. We conclude that closure occurs during the rate-limiting catalytic step of decapping, juxtaposing the cap-binding region of each domain to form a composite active site. This work suggests a model for regulation of decapping, where coactivators trigger decapping by stabilizing a labile composite active site. PMID:20711189

  2. Final Site-Wide Environmental Impact Statement for the Y-12 National Security Complex

    SciTech Connect

    N /A

    2001-11-02

    The National Nuclear Security Administration (NNSA) a separately organized agency within the U.S. Department of Energy (DOE) is responsible for providing the Nation with nuclear weapons and ensuring that those nuclear weapons remain safe, secure, and reliable. As one of the DOE major production facilities, the Y-12 National Security Complex has been DOE's primary site for enriched uranium processing and storage, and one of the manufacturing facilities for maintaining the U.S. nuclear weapons stockpile. In response to the end of the Cold War and changes in the world's political regimes, the emphasis of the U.S. weapons program has shifted dramatically over the past few years from developing and producing new weapons to dismantlement and maintenance of a smaller, enduring stockpile. The ''Stockpile Stewardship and Management Programmatic Environmental Impact Statement'' [SSM PEIS], DOE/EIS-0236, issued in September 1996, evaluated alternatives for maintaining the safety and reliability of the nuclear weapons stockpile without underground nuclear testing or production of new-design weapons. In the SSM PEIS Record of Decision (ROD), DOE decided to maintain the national security missions at the Y-12 National Security Complex, but to downsize Y-12 consistent with reduced requirements. These national security missions include (1) maintaining the capability and capacity to fabricate secondaries, limited life components, and case parts for nuclear response; (2) evaluating components and subsystems returned from the stockpile; (3) storing enriched uranium that is designated for national security purposes; (4) storing depleted uranium and lithium parts; (5) dismantling nuclear weapons secondaries returned from the stockpile; (6) processing uranium and lithium (which includes chemical recovery, purification, and conversion of enriched uranium and lithium to a form suitable for long-term storage and/or further use); and (7) providing support to weapons laboratories. During the

  3. Catalase evolved to concentrate H2O2 at its active site.

    PubMed

    Domínguez, Laura; Sosa-Peinado, Alejandro; Hansberg, Wilhelm

    2010-08-01

    Catalase is a homo-tetrameric enzyme that has its heme active site deeply buried inside the protein. Its only substrate, hydrogen peroxide (H2O2), reaches the heme through a 45 A-long channel. Large-subunit catalases, but not small-subunit catalases, have a loop (gate loop) that interrupts the major channel. Two accesses lead to a gate that opens the final section of the channel to the heme; gates from the R-related subunits are interconnected. Using molecular dynamic simulations of the Neurospora crassa catalase-1 tetramer in a box of water (48,600 molecules) or 6M H2O2, it is shown that the number of H2O2 molecules augments at the surface of the protein and in the accesses to the gate and the final section of the channel. Increase in H2O2 is due to the prevalence and distribution of amino acids that have an increased residency for H2O2 (mainly histidine, proline and charged residues), which are localized at the protein surface and the accesses to the gate. In the section of the channel from the heme to the gate, turnover rate of water molecules was faster than for H2O2 and increased residence sites for water and H2O2 were determined. In the presence of H2O2, the exclusion of water molecules from a specific site suggests a mechanism that could contend with the competing activity of water, allowing for catalase high kinetic efficiency.

  4. Low severity conversion of activated coal. Final report

    SciTech Connect

    Hirschon, A.S.; Ross, D.S.

    1990-01-01

    The results suggest that coal contains regions with structural components significantly reactive under the hydrothermal environment. Although the specific mechanism for this process remains to be developed, this activity is reminiscent of findings in studies of accelerated maturation of oil shale, where hydrothermal treatment (hydrous pyrolysis) leads to the production of petroleum hydrocarbons. In line with what has been seen in the oil shale work, the pretreatment-generated hydrocarbons and phenols appear to represent a further or more complete maturation of some fraction of the organic material within the coal. These observations could have an impact in two areas. The first is in the area of coal structure, where immature, reactive regions have not been included in the structures considered at present. The second area of interest is the more practical one of conversions to coal liquids and pyrolytic tars. It seems clear that the hydrothermal pretreatment changes the coal in some manner that favorably affects the product quality substantially and, as in the CO/water liquefaction case, favorably affects the yields. The conversions of coals of lower rank, i.e., less mature coals, could particularly benefit in terms of both product quality and product quantity. The second portion of this project also shows important benefits to coal conversion technology. It deals with synthesizing catalysts designed to cleave the weak links in the coal structure and then linking these catalysts with the pretreatment methods in Task 2. The results show that highly dispersed catalysts can effectively be used to increase the yields of soluble material. An important aspect of highly dispersed catalysts are that they can effectively catalyze coal conversion even in poor liquefaction solvents, thus making them very attractive in processes such as coprocessing where inexpensive liquefaction media such as resids are used.

  5. 317/319 Phytoremediation site monitoring report - 2009 growing season : final report.

    SciTech Connect

    Negri, C .N.; Benda, P. L.; Gopalakrishnan, G.; Energy Systems

    2010-02-10

    In 1999, Argonne National Laboratory (Argonne) designed and installed a series of engineered plantings consisting of a vegetative cover system and approximately 800 hybrid poplars and willows rooting at various predetermined depths. The plants were installed using various methods including Applied Natural Science's TreeWell{reg_sign} system. The goal of the installation was to protect downgradient surface and groundwater by intercepting the contaminated groundwater with the tree roots, removing moisture from the upgradient soil area, reducing water infiltration, preventing soil erosion, degrading and/or transpiring the residual volatile organic compounds (VOCs), and removing tritium from the subsoil and groundwater. This report presents the results of the monitoring activities conducted by Argonne's Energy Systems (ES) Division in the growing season of 2009. Monitoring of the planted trees began soon after the trees were installed in 1999 and has been conducted every summer since then. As the trees grew and consolidated their growth into the contaminated soil and groundwater, their exposure to the contaminants was progressively shown through tissue sampling. During the 2009 sampling campaign, VOC concentrations found in the French Drain area were in general consistent with or slightly lower than the 2008 results. Additionally, closely repeated, stand wide analyses showed contaminant fluctuations that may indicate short-term contaminant depletion in the area of interest of roots. This data will be useful to determine short-term removal rate by the trees. As in previous years, levels in the Hydraulic Control Area were close to background levels except for a few exceptions.

  6. Characterization of the interactions between the active site of a protein tyrosine kinase and a divalent metal activator

    PubMed Central

    Lin, Xiaofeng; Ayrapetov, Marina K; Sun, Gongqin

    2005-01-01

    Background Protein tyrosine kinases are important enzymes for cell signalling and key targets for anticancer drug discovery. The catalytic mechanisms of protein tyrosine kinase-catalysed phosphorylation are not fully understood. Protein tyrosine kinase Csk requires two Mg2+ cations for activity: one (M1) binds to ATP, and the other (M2) acts as an essential activator. Results Experiments in this communication characterize the interaction between M2 and Csk. Csk activity is sensitive to pH in the range of 6 to 7. Kinetic characterization indicates that the sensitivity is not due to altered substrate binding, but caused by the sensitivity of M2 binding to pH. Several residues in the active site with potential of binding M2 are mutated and the effect on metal activation studied. An active mutant of Asn319 is generated, and this mutation does not alter the metal binding characteristics. Mutations of Glu236 or Asp332 abolish the kinase activity, precluding a positive or negative conclusion on their role in M2 coordination. Finally, the ability of divalent metal cations to activate Csk correlates to a combination of ionic radius and the coordination number. Conclusion These studies demonstrate that M2 binding to Csk is sensitive to pH, which is mainly responsible for Csk activity change in the acidic arm of the pH response curve. They also demonstrate critical differences in the metal activator coordination sphere in protein tyrosine kinase Csk and a protein Ser/Thr kinase, the cAMP-dependent protein kinase. They shed light on the physical interactions between a protein tyrosine kinase and a divalent metal activator. PMID:16305747

  7. Characterization of Active Site Residues of Nitroalkane Oxidase†

    PubMed Central

    Valley, Michael P.; Fenny, Nana S.; Ali, Shah R.; Fitzpatrick, Paul F.

    2010-01-01

    The flavoenzyme nitroalkane oxidase catalyzes the oxidation of primary and secondary nitrolkanes to the corresponding aldehydes and ketones plus nitrite. The structure of the enzyme shows that Serl71 forms a hydrogen bond to the flavin N5, suggesting that it plays a role in catalysis. Cys397 and Tyr398 were previously identified by chemical modification as potential active site residues. To more directly probe the roles of these residues, the S171A, S171V, S171T, C397S, and Y398F enzymes have been characterized with nitroethane as substrate. The C397S and Y398 enzymes were less stable than the wild-type enzyme, and the C397S enzyme routinely contained a substoichiometric amount of FAD. Analysis of the steady-state kinetic parameters for the mutant enzymes, including deuterium isotope effects, establishes that all of the mutations result in decreases in the rate constants for removal of the substrate proton by ~5-fold and decreases in the rate constant for product release of ~2-fold. Only the S171V and S171T mutations alter the rate constant for flavin oxidation. These results establish that these residues are not involved in catalysis, but rather are required for maintaining the protein structure. PMID:20056514

  8. Detection limit for activation measurements in ultralow background sites

    NASA Astrophysics Data System (ADS)

    Trache, Livius; Chesneanu, D.; Margineanu, R.; Pantelica, A.; Ghita, D. G.; Burducea, I.; Straticiuc, M.; Tang, X. D.

    2014-09-01

    We used 12C +13C fusion at the beam energies E = 6, 7 and 8 MeV to determine the sensitivity and the limits of activation method measurements in ultralow background sites. A 13C beam of 0.5 μA from the 3 MV Tandem accelerator of the Horia Hulubei National Institute of Physics and Nuclear Engineering - IFIN HH impinged on thick graphite targets. After about 24 hrs of irradiation targets were measured in two different laboratories: one with a heavy shielded Ge detector in the institute (at the surface) and one located underground in the microBequerel laboratory, in the salt mine of Slanic-Prahova, Romania. The 1369- and 2754 keV peaks from 24Na deactivation were clearly observed in the γ-ray spectra obtained for acquisitions lasting a few hours, or a few days. Determination of the detection limit in evaluating the cross sections for the target irradiated at Ec . m = 3 MeV indicates the fact that it is possible to measure gamma spectrum in underground laboratory down to Ec . m = 2 . 6 MeV. Cleaning the spectra with beta-gamma coincidences and increasing beam intensity 20 times will take as further down. The measurements are motivated by the study of the 12 C +12 C reaction at astrophysical energies.

  9. Disturbance opens recruitment sites for bacterial colonization in activated sludge.

    PubMed

    Vuono, David C; Munakata-Marr, Junko; Spear, John R; Drewes, Jörg E

    2016-01-01

    Little is known about the role of immigration in shaping bacterial communities or the factors that may dictate success or failure of colonization by bacteria from regional species pools. To address these knowledge gaps, the influence of bacterial colonization into an ecosystem (activated sludge bioreactor) was measured through a disturbance gradient (successive decreases in the parameter solids retention time) relative to stable operational conditions. Through a DNA sequencing approach, we show that the most abundant bacteria within the immigrant community have a greater probability of colonizing the receiving ecosystem, but mostly as low abundance community members. Only during the disturbance do some of these bacterial populations significantly increase in abundance beyond background levels and in few cases become dominant community members post-disturbance. Two mechanisms facilitate the enhanced enrichment of immigrant populations during disturbance: (i) the availability of resources left unconsumed by established species and (ii) the increased availability of niche space for colonizers to establish and displace resident populations. Thus, as a disturbance decreases local diversity, recruitment sites become available to promote colonization. This work advances our understanding of microbial resource management and diversity maintenance in complex ecosystems.

  10. A phosphorylation site in the ftz homeodomain is required for activity.

    PubMed Central

    Dong, J; Hung, L H; Strome, R; Krause, H M

    1998-01-01

    The Drosophila homeodomain-containing protein Fushi tarazu (Ftz) is expressed sequentially in the embryo, first in alternate segments, then in specific neuroblasts and neurons in the central nervous system, and finally in parts of the gut. During these different developmental stages, the protein is heavily phosphorylated on different subsets of Ser and Thr residues. This stage-specific phosphorylation suggests possible roles for signal transduction pathways in directing tissue-specific Ftz activities. Here we show that one of the Ftz phosphorylation sites, T263 in the N-terminus of the Ftz homeodomain, is phosphorylated in vitro by Drosophila embryo extracts and protein kinase A. In the embryo, mutagenesis of this site to the non-phosphorylatable residue Ala resulted in loss of ftz-dependent segments. Conversely, substitution of T263 with Asp, which is also non-phosphorylatable, but which successfully mimics phosphorylated residues in a number of proteins, rescued the mutant phenotype. This suggests that T263 is in the phosphorylated state when functioning normally in vivo. We also demonstrate that the T263 substitutions of Ala and Asp do not affect Ftz DNA-binding activity in vitro, nor do they affect stability or transcriptional activity in transfected S2 cells. This suggests that T263 phosphorylation is most likely required for a homeodomain-mediated interaction with an embryonically expressed protein. PMID:9545243

  11. FY02 Final Report on Phytoremediation of Chlorinated Ethenes in Southern Sector Sediments of the Savannah River Site

    SciTech Connect

    Brigmon, R..L.

    2004-01-30

    This final report details the operations and results of a 3-year Seepline Phytoremediation Project performed adjacent to Tims Branch, which is located in the Southern Sector of the Savannah River Site (SRS) A/M Area. Phytoremediation is a process where interactions between vegetation, associated microorganisms, and the host substrate combine to effectively degrade contaminated soils, sediments, and groundwater. Phytoremediation is a rapidly developing technology that shows promise for the effective and safe cleanup of certain hazardous wastes. It has the potential to remediate numerous volatile organic compounds (VOCs). Extensive characterization work has demonstrated that two VOCs, tetrachloroethylene (PCE) and trichloroethylene (TCE) are the major components of the VOC-contaminated groundwater that is migrating through the Southern Sector and Tims Branch seepline area (WSRC, 1999). The PCE and TCE are chlorinated ethenes (CE), and have been detected in seepline soils and ground water adjacent to the ecologically-sensitive Tims Branch seepline area.

  12. 40 CFR 61.154 - Standard for active waste disposal sites.

    Code of Federal Regulations, 2012 CFR

    2012-07-01

    ... 40 Protection of Environment 9 2012-07-01 2012-07-01 false Standard for active waste disposal... for Asbestos § 61.154 Standard for active waste disposal sites. Each owner or operator of an active... visible emissions to the outside air from any active waste disposal site where asbestos-containing...

  13. 40 CFR 61.154 - Standard for active waste disposal sites.

    Code of Federal Regulations, 2014 CFR

    2014-07-01

    ... 40 Protection of Environment 9 2014-07-01 2014-07-01 false Standard for active waste disposal... for Asbestos § 61.154 Standard for active waste disposal sites. Each owner or operator of an active... visible emissions to the outside air from any active waste disposal site where asbestos-containing...

  14. Installation restoration program site investigation. Gulfport Field Training Site, Mississippi Air National Guard Gulfport-Biloxi Regional Airport Gulfport, Mississippi. Volume 1. Final report

    SciTech Connect

    1992-12-01

    Site Investigation Report, Volume: 1. A Site Investigation was performed at three sites at the Combat Readiness Training Center, Gulfport-Bolixi. The three sites investigated are the: Former Fire Training Area (Site 1), the Former JP-4 Bulk Storage Area, Mill Road (Site 2), and the Motor Pool Above-Ground Diesel Fuel Storage Tank Area (Site 3). The findings of this investigation recommended further investigation at the Fire Training Area and the JP-4 Bulk Storage Tank. At Site 3 the levels of contamination did not represent a risk to human health or the environment; therefore, no further action was recommended.

  15. 10 CFR 63.16 - Review of site characterization activities. 2

    Code of Federal Regulations, 2010 CFR

    2010-01-01

    ... IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Licenses Preapplication Review § 63.16 Review of... conduct of site characterization activities at the Yucca Mountain site, DOE shall report the nature and... activities at the Yucca Mountain site, NRC staff shall be permitted to visit and inspect the locations...

  16. 10 CFR 63.16 - Review of site characterization activities. 2

    Code of Federal Regulations, 2011 CFR

    2011-01-01

    ... IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Licenses Preapplication Review § 63.16 Review of... conduct of site characterization activities at the Yucca Mountain site, DOE shall report the nature and... activities at the Yucca Mountain site, NRC staff shall be permitted to visit and inspect the locations...

  17. 10 CFR 63.16 - Review of site characterization activities. 2

    Code of Federal Regulations, 2013 CFR

    2013-01-01

    ... IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Licenses Preapplication Review § 63.16 Review of... conduct of site characterization activities at the Yucca Mountain site, DOE shall report the nature and... activities at the Yucca Mountain site, NRC staff shall be permitted to visit and inspect the locations...

  18. 10 CFR 63.16 - Review of site characterization activities. 2

    Code of Federal Regulations, 2012 CFR

    2012-01-01

    ... IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Licenses Preapplication Review § 63.16 Review of... conduct of site characterization activities at the Yucca Mountain site, DOE shall report the nature and... activities at the Yucca Mountain site, NRC staff shall be permitted to visit and inspect the locations...

  19. 10 CFR 63.16 - Review of site characterization activities. 2

    Code of Federal Regulations, 2014 CFR

    2014-01-01

    ... IN A GEOLOGIC REPOSITORY AT YUCCA MOUNTAIN, NEVADA Licenses Preapplication Review § 63.16 Review of... conduct of site characterization activities at the Yucca Mountain site, DOE shall report the nature and... activities at the Yucca Mountain site, NRC staff shall be permitted to visit and inspect the locations...

  20. Activity of N-coordinated multi-metal-atom active site structures for Pt-free oxygen reduction reaction catalysis: Role of *OH ligands

    PubMed Central

    Holby, Edward F.; Taylor, Christopher D.

    2015-01-01

    We report calculated oxygen reduction reaction energy pathways on multi-metal-atom structures that have previously been shown to be thermodynamically favorable. We predict that such sites have the ability to spontaneously cleave the O2 bond and then will proceed to over-bind reaction intermediates. In particular, the *OH bound state has lower energy than the final 2 H2O state at positive potentials. Contrary to traditional surface catalysts, this *OH binding does not poison the multi-metal-atom site but acts as a modifying ligand that will spontaneously form in aqueous environments leading to new active sites that have higher catalytic activities. These *OH bound structures have the highest calculated activity to date. PMID:25788358

  1. Activity of N-coordinated multi-metal-atom active site structures for Pt-free oxygen reduction reaction catalysis: Role of *OH ligands

    DOE PAGES

    Holby, Edward F.; Taylor, Christopher D.

    2015-03-19

    We report calculated oxygen reduction reaction energy pathways on multi-metal-atom structures that have previously been shown to be thermodynamically favorable. We predict that such sites have the ability to spontaneously cleave the O₂ bond and then will proceed to over-bind reaction intermediates. In particular, the *OH bound state has lower energy than the final 2 H₂O state at positive potentials. Contrary to traditional surface catalysts, this *OH binding does not poison the multi-metal-atom site but acts as a modifying ligand that will spontaneously form in aqueous environments leading to new active sites that have higher catalytic activities. These *OH boundmore » structures have the highest calculated activity to date.« less

  2. Activity of N-coordinated multi-metal-atom active site structures for Pt-free oxygen reduction reaction catalysis: Role of *OH ligands

    SciTech Connect

    Holby, Edward F.; Taylor, Christopher D.

    2015-03-19

    We report calculated oxygen reduction reaction energy pathways on multi-metal-atom structures that have previously been shown to be thermodynamically favorable. We predict that such sites have the ability to spontaneously cleave the O₂ bond and then will proceed to over-bind reaction intermediates. In particular, the *OH bound state has lower energy than the final 2 H₂O state at positive potentials. Contrary to traditional surface catalysts, this *OH binding does not poison the multi-metal-atom site but acts as a modifying ligand that will spontaneously form in aqueous environments leading to new active sites that have higher catalytic activities. These *OH bound structures have the highest calculated activity to date.

  3. Activity of N-coordinated multi-metal-atom active site structures for Pt-free oxygen reduction reaction catalysis: Role of *OH ligands

    NASA Astrophysics Data System (ADS)

    Holby, Edward F.; Taylor, Christopher D.

    2015-03-01

    We report calculated oxygen reduction reaction energy pathways on multi-metal-atom structures that have previously been shown to be thermodynamically favorable. We predict that such sites have the ability to spontaneously cleave the O2 bond and then will proceed to over-bind reaction intermediates. In particular, the *OH bound state has lower energy than the final 2 H2O state at positive potentials. Contrary to traditional surface catalysts, this *OH binding does not poison the multi-metal-atom site but acts as a modifying ligand that will spontaneously form in aqueous environments leading to new active sites that have higher catalytic activities. These *OH bound structures have the highest calculated activity to date.

  4. Robotics and Automation Activities at the Savannah River Site: A Site Report for SUBWOG 39F

    SciTech Connect

    Teese, G.D.

    1995-09-28

    The Savannah River Site has successfully used robots, teleoperators, and remote video to reduce exposure to ionizing radiation, improve worker safety, and improve the quality of operations. Previous reports have described the use of mobile teleoperators in coping with a high level liquid waste spill, the removal of highly contaminated equipment, and the inspection of nuclear reactor vessels. This report will cover recent applications at the Savannah River, as well as systems which SRS has delivered to other DOE site customers.

  5. GAS HYDRATES AT TWO SITES OF AN ACTIVE CONTINENTAL MARGIN.

    USGS Publications Warehouse

    Kvenvolden, K.A.

    1985-01-01

    Sediment containing gas hydrates from two distant Deep Sea Drilling Project sites (565 and 568), located about 670 km apart on the landward flank of the Middle America Trench, was studied to determine the geochemical conditions that characterize the occurrence of gas hydrates. Site 565 was located in the Pacific Ocean offshore the Nicoya Peninsula of Costa Rica in 3,111 m of water. The depth of the hole at this site was 328 m, and gas hydrates were recovered from 285 and 319 m. Site 568 was located about 670 km to the northwest offshore Guatemala in 2,031 m of water. At this site the hole penetrated to 418 m, and gas hydrates were encountered at 404 m.

  6. Interannual active layer thermal and dynamics evolution at the crater Lake CALM site, Deception Island (Antarctica).

    NASA Astrophysics Data System (ADS)

    Ramos, Miguel; Vieira, Gonzalo; Ángel De Pablo, Miguel; Molina, Antonio; Abramov, Andrey

    2015-04-01

    Deception Island, is an active strato-volcano on South Shetland Archipelago of Antarctica (62° 55' 0″ S, 60° 37' 0″ W), is a cold region with harsh remote and hostile environmental conditions. The permafrost and active layer existence, and the cold climate conditions together with volcanic material with height water content inside made this region of the Earth a perfect site to study the active layer and permafrost evolution involved in the Circumpolar Active Layer South (CALM-S) program. The active layer is measured in late January or firs february (during the end of the thaw period) at the "Crater Lake" CALM site (62°58'06.7''; 60°40'44.8'') on Deception Island, Antarctica, at the period 2006 to 2014 we obtained a mean annual value of 29,7±2 cm. In this paper, we describe the spatial active layer thickness distribution and report the reduction on the mean thickness between February 2006 and 2014. Below the active layer, permafrost could be also reported (with a mean thickness of 4.5± 0.5 m.) based on the temperature data acquired by sensors installed at different depth inside the soil; three different shallow boreholes was drilled (1.0 m., 1.6 m., 4.5 m. in depth) and we have been registered its temperature gradient at the 2010 to 2013 period. Here we use all those data 1) to describe the thermal behavior of the permafrost at the CALM site, and 2) to describe its evolution (aggradation/degradation) along fourteen years of continuous measurements. We develop this study, to known the thermal behavior of the permafrost and the active layer related with the air/soil interaction being one of the most important factors the snow layer that was measured by the installation of termo-snowmeters with the complement of an automatic digital camera during the 2008 to 2014 period. On the other hand, the pyroclastics soil materials has a very high values of water content then the latent heat in the freezing/thawing process controls the active layer evolution and the

  7. EPA Finalizes Plan to Address Contaminated Groundwater at Curtis Specialty Papers Superfund Site in Milford Borough and Alexandria Township, N.J.

    EPA Pesticide Factsheets

    (New York, N.Y.) The U.S. Environmental Protection Agency has finalized a plan to clean up contaminated groundwater at the Curtis Specialty Papers Superfund site in Milford Borough and Alexandria Township, New Jersey. The site includes the former Milford P

  8. Lidar research activities and observations at NARL site, Gadanki, India

    NASA Astrophysics Data System (ADS)

    Yellapragada, Bhavani Kumar

    2016-05-01

    The National Atmospheric Research Laboratory (NARL), a unit of Department of Space (DOS), located at Gadanki village (13.5°N, 79.2°E, 370 m AMSL) in India, is involved in the development of lidar remote sensing technologies for atmospheric research. Several advanced lidar technologies employing micropulse, polarization, Raman and scanning have been developed at this site and demonstrated for atmospheric studies during the period between 2008 and 2015. The technology of micropulse lidar, operates at 532 nm wavelength, was successfully transferred to an industry and the commercial version has been identified for Indian Lidar network (I-LINK) programme. Under this lidar network activity, several lidar units were installed at different locations in India to study tropospheric aerosols and clouds. The polarization sensitive lidar technology was realized using a set of mini photomultiplier tube (PMT) units and has the capability to operate during day and night without a pause. The lidar technology uses a compact flashlamp pumped Qswitched laser and employs biaxial configuration between the transmitter and receiver units. The lidar technology has been utilized for understanding the polarization characteristics of boundary layer aerosols during the mixed layer development. The demonstrated Raman lidar technology, uses the third harmonic wavelength of Nd:YAG laser, provides the altitude profiles of aerosol backscattering, extinction and water vapor covering the boundary layer range and allows operation during nocturnal periods. The Raman lidar derived height profiles of aerosol backscattering and extinction coefficient, lidar ratio, and watervapor mixing ratio inform the tropical boundary layer aerosol characteristics. The scanning lidar technology uses a near infrared laser wavelength for probing the lower atmosphere and has been utilized for high resolution cloud profiling during convective periods. The lidar technology is also used for rain rate measurement during

  9. Dynamically achieved active site precision in enzyme catalysis.

    PubMed

    Klinman, Judith P

    2015-02-17

    CONSPECTUS: The grand challenge in enzymology is to define and understand all of the parameters that contribute to enzymes' enormous rate accelerations. The property of hydrogen tunneling in enzyme reactions has moved the focus of research away from an exclusive focus on transition state stabilization toward the importance of the motions of the heavy atoms of the protein, a role for reduced barrier width in catalysis, and the sampling of a protein conformational landscape to achieve a family of protein substates that optimize enzyme-substrate interactions and beyond. This Account focuses on a thermophilic alcohol dehydrogenase for which the chemical step of hydride transfer is rate determining across a wide range of experimental conditions. The properties of the chemical coordinate have been probed using kinetic isotope effects, indicating a transition in behavior below 30 °C that distinguishes nonoptimal from optimal C-H activation. Further, the introduction of single site mutants has the impact of either enhancing or eliminating the temperature dependent transition in catalysis. Biophysical probes, which include time dependent hydrogen/deuterium exchange and fluorescent lifetimes and Stokes shifts, have also been pursued. These studies allow the correlation of spatially resolved transitions in protein motions with catalysis. It is now possible to define a long-range network of protein motions in ht-ADH that extends from a dimer interface to the substrate binding domain across to the cofactor binding domain, over a distance of ca. 30 Å. The ongoing challenge to obtaining spatial and temporal resolution of catalysis-linked protein motions is discussed.

  10. Probing the active site of cinnamoyl CoA reductase 1 (Ll-CCRH1) from Leucaena leucocephala.

    PubMed

    Sonawane, Prashant; Patel, Krunal; Vishwakarma, Rishi Kishore; Srivastava, Sameer; Singh, Somesh; Gaikwad, Sushama; Khan, Bashir M

    2013-09-01

    Lack of three dimensional crystal structure of cinnamoyl CoA reductase (CCR) limits its detailed active site characterization studies. Putative active site residues involved in the substrate/NADPH binding and catalysis for Leucaena leucocephala CCR (Ll-CCRH1; GenBank: DQ986907) were identified by amino acid sequence alignment and homology modeling. Putative active site residues and proximal H215 were subjected for site directed mutagenesis, and mutated enzymes were expressed, purified and assayed to confirm their functional roles. Mutagenesis of S136, Y170 and K174 showed complete loss of activity, indicating their pivotal roles in catalysis. Mutant S212G exhibited the catalytic efficiencies less than 10% of wild type, showing its indirect involvement in substrate binding or catalysis. R51G, D77G, F30V and I31N double mutants showed significant changes in Km values, specifying their roles in substrate binding. Finally, chemical modification and substrate protection studies corroborated the presence Ser, Tyr, Lys, Arg and carboxylate group at the active site of Ll-CCRH1.

  11. Active-site zinc ligands and activated H2O of zinc enzymes.

    PubMed Central

    Vallee, B L; Auld, D S

    1990-01-01

    The x-ray crystallographic structures of 12 zinc enzymes have been chosen as standards of reference to identify the ligands to the catalytic and structural zinc atoms of other members of their respective enzyme families. Universally, H2O is a ligand and critical component of the catalytically active zinc sites. In addition, three protein side chains bind to the catalytic zinc atom, whereas four protein ligands bind to the structural zinc atom. The geometry and coordination number of zinc can vary greatly to accommodate particular ligands. Zinc forms complexes with nitrogen and oxygen just as readily as with sulfur, and this is reflected in catalytic zinc sites having a binding frequency of His much greater than Glu greater than Asp = Cys, three of which bind to the metal atom. The systematic spacing between the ligands is striking. For all catalytic zinc sites except the coenzyme-dependent alcohol dehydrogenase, the first two ligands are separated by a "short-spacer" consisting of 1 to 3 amino acids. These ligands are separated from the third ligand by a "long spacer" of approximately 20 to approximately 120 amino acids. The spacer enables formation of a primary bidentate zinc complex, whereas the long spacer contributes flexibility to the coordination sphere, which can poise the zinc for catalysis as well as bring other catalytic and substrate binding groups into apposition with the active site. The H2O is activated by ionization, polarization, or poised for displacement. Collectively, the data imply that the preferred mechanistic pathway for activating the water--e.g., zinc hydroxide or Lewis acid catalysis--will be determined by the identity of the other three ligands and their spacing. Images PMID:2104979

  12. Remedial Action Plan and Site Design for stabilization of the inactive Uranium Mill Tailings sites at Slick Rock, Colorado: Appendix C to Attachment 3, Calculations. Final

    SciTech Connect

    1995-09-01

    This volume contains calculations for: Slick Rock processing sites background ground water quality; Slick Rock processing sites lysimeter water quality; Slick Rock processing sites on-site and downgradient ground water quality; Slick Rock disposal site background water quality; Burro Canyon disposal site, Slick Rock, Colorado, average hydraulic gradients and average liner ground water velocities in the upper, middle, and lower sandstone units of the Burro Canyon formation; Slick Rock--Burro Canyon disposal site, Burro Canyon pumping and slug tests--analyses; water balance and surface contours--Burro Canyon disposal cell; and analytical calculation of drawdown in a hypothetical well completed in the upper sandstone unit of the Burro Canyon formation.

  13. Chemical-Stockpile Disposal Program. Risk analysis of the disposal of chemical munitions at regional or national sites. Final report, 3 February 1986-25 August 1987

    SciTech Connect

    Barsell, A.W.; Bellis, E.A.; Bolig, C.A.; Deremer, R.K.; Everline, C.J.

    1987-08-01

    This document was prepared for the U.S. Army to support the Final Programmatic Environmental Impact Statement for the Chemical Stockpile Disposal Program. This report describes the results of a comprehensive probabilistic assessment of the frequency and magnitude of chemical agent release for the storage, handling, on-site transportation, off-site transportation, and chemical-demilitarization plant operations associated with the disposal of the chemical stockpile at two regional disposal sites or at a single national disposal site. Rail transportation from seven sites, air transportation from two sites and water transportation from one site were the off-site transportation modes analyzed. Both internal accident initiators (e.g., human error, equipment malfunction) and external accident initiators (e.g., earthquakes, airplane crashes) were included in the analysis.

  14. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Mexican Hat, Utah: Text, Appendices A--C. Final report

    SciTech Connect

    1988-07-01

    This Remedial Action Plan (RAP) has been developed to serve a two- fold purpose. It presents the activities proposed by the Department of Energy (DOE) to accomplish long-term stabilization and control of the residual radioactive materials (RRM) from Monument Valley Arizona, and Mexican Hat, Utah, at the Mexican Hat disposal site. It also serves to document the concurrence of both the Navajo Nation and the Nuclear Regulatory Commission (NRC) in the remedial action. This agreement, upon execution by DOE and the Navajo Nation and concurrence by the NRC, becomes Appendix B of the Cooperative Agreement. This document has been structured to provide a comprehensive understanding of the remedial action proposed for the Monument Valley and Mexican Hat sites. It includes specific design and construction requirements for the remedial action. Pertinent information and data are included with reference given to the supporting documents. Appendices A,B, and C are provided as part of this document. Appendix A presents regulatory compliance issues, Appendix B provides details of the engineering design, and Appendix C presents the radiological support plan.

  15. Reactive characterization as a probe of the nature of catalytic sites. Final report, April 15, 1988--February 14, 1993

    SciTech Connect

    Brenner, A.

    1998-05-01

    The primary goal of the last year of the research program was to create a new type of selective heterogeneous catalyst. The new catalysts were synthesized, their unusual selectivity assessed by a model reaction, and some of the parameters which are important in creating unusual selectivity in these catalysts determined. Near the end of this proposal, considerable excitement was generated by the discovery of high temperature superconductors. It was decided to briefly investigate the activity of some superconductors and related cuprates. This research was done in concert with a project funded by Ford Motor Company. Catalysts were investigated for two reactions useful in pollution control: CO oxidation and NO reduction. In addition, some stoichiometric measurements of the oxygen content of superconductors and related cuprates were made using a TPR apparatus in the lab. In addition, some experiments were done with the objective of preparing novel MO-Pd/Al{sub 2}O{sub 3} catalysts in which the Mo and Pd were in close contact. These catalysts have the potential of replacing much more expensive rhodium containing catalysts which are currently used for emissions control. Progress on the following is described: H{sub 2}-D{sub 2} exchange on transition metals; New method of determining the number of active sites; New method of determining the hydroxyl content of catalysts; H{sub 2}-D{sub 2} exchange on metal oxides; Reactive characterization and atomic isolation of active sites; Site isolated catalysts synthesized by selective poisoning; Catalysts prepared from high temperature superconductors; Mixed metal Pd-Mo catalysts; and Selective reduction of nitric oxide.

  16. Lethal Factor Active-Site Mutations Affect Catalytic Activity In Vitro

    PubMed Central

    Hammond, S. E.; Hanna, P. C.

    1998-01-01

    The lethal factor (LF) protein of Bacillus anthracis lethal toxin contains the thermolysin-like active-site and zinc-binding consensus motif HEXXH (K. R. Klimpel, N. Arora, and S. H. Leppla, Mol. Microbiol. 13:1093–1100, 1994). LF is hypothesized to act as a Zn2+ metalloprotease in the cytoplasm of macrophages, but no proteolytic activities have been previously shown on any target substrate. Here, synthetic peptides are hydrolyzed by LF in vitro. Mass spectroscopy and peptide sequencing of isolated cleavage products separated by reverse-phase high-pressure liquid chromatography indicate that LF seems to prefer proline-containing substrates. Substitution mutations within the consensus active-site residues completely abolish all in vitro catalytic functions, as does addition of 1,10-phenanthroline, EDTA, and certain amino acid hydroxamates, including the novel zinc metalloprotease inhibitor ZINCOV. In contrast, the protease inhibitors bestatin and lysine CMK, previously shown to block LF activity on macrophages, did not block LF activity in vitro. These data provide the first direct evidence that LF may act as an endopeptidase. PMID:9573135

  17. The yeast regulator of transcription protein Rtr1 lacks an active site and phosphatase activity.

    PubMed

    Xiang, Kehui; Manley, James L; Tong, Liang

    2012-07-10

    The activity of RNA polymerase II (Pol II) is controlled in part by the phosphorylation state of the C-terminal domain (CTD) of its largest subunit. Recent reports have suggested that yeast regulator of transcription protein, Rtr1, and its human homologue RPAP2, possess Pol II CTD Ser5 phosphatase activity. Here we report the crystal structure of Kluyveromyces lactis Rtr1, which reveals a new type of zinc finger protein and does not have any close structural homologues. Importantly, the structure does not show evidence of an active site, and extensive experiments to demonstrate its CTD phosphatase activity have been unsuccessful, suggesting that Rtr1 has a non-catalytic role in CTD dephosphorylation.

  18. Installation restoration program site investigation. Gulfport Field Training Site, Mississippi Air National Guard Gulfport-Biloxi Regional Airport Gulfport, Mississippi. Volume 2. Final report

    SciTech Connect

    1992-12-01

    Site Investigation Report, Volume: 2. A Site Investigation was performed at 3 sites at the Combat Readiness Training Center, Gulfport-Bolixi. The 3 sites investigated are the: Former Fire Training Area (Site 1), the Former JP-4 Bulk Storage Area, Mill Road (Site 2), and the Motor Pool Above-Ground Diesel Fuel Storage Tank Area (Site 3). The findings of this investigation recommended further investigation at the Fire Training Area and the JP-4 Bulk Storage Tank. At Site 3 the levels of contamination did not represent a risk to human health or the environment; therefore, no further action was recommended. Volume two of this report consisted of the following Appendixes: Site Photographs (A), Well Inventory (B), Boring Logs (C), CSL Technical Memorandum (D), Data Review and Validation (E), GPS Memorandum (F), Level C Analytical Data Summary Tables (G), Slug Test (H), Special-Status Species (I), and Representative Species of Less Mobile Fish and Wildlife (J).

  19. Installation restoration program final remedial investigation report IRP sites 8 and 10. 151st air refueling group Utah Air National Guard, Salt Lake City, Utah. Final report

    SciTech Connect

    1996-06-01

    This report presents the results from a Remedial Investigation (RI) for two sites at the Utah Air National Guard (UANG) Base located in Salt Lake City, Utah. The two sites investigated are identified as Installation Restoration Program (IRP) Site 8, a former underground storage tank (UST) location, and IRP Site 10, an existing petroleum, oil, and lubricants (POL) yard. The RI was conducted as outlined in the Remedial Investigation/Feasibility Study (RI/FS) Work Plan prepared by Stone Webster and submitted to and approved by the ANG in May 1993. The field work associated with the RI was performed in June, July, and August 1995.

  20. Remedial action plan and site design for stabilization of the Inactive Uranium Mill Tailings Site, Maybell, Colorado. Final report, Appendixes to attachment 3

    SciTech Connect

    Not Available

    1994-06-01

    This document contains supporting appendices to attachment 3 for the remedial action and site stabilization plan for Maybell, Colorado UMTRA site. Appendix A includes the Hydrological Services Calculations and Appendix B contains Ground Water Quality by Location data.

  1. Final Report: Technical Assistance for the Kearsarge Metallurgical Corporation Superfund Site, Conway, New Hampshire, EPA Region 1

    EPA Pesticide Factsheets

    This report reviews and provides recommendations for a long-term groundwater monitoring network for the Kearsarge Metallurgical Corporation Superfund site (KMC site). The KMC site is a former foundry and metal fabrication facility in Conway, New Hampshire.

  2. Mining Sites on the National Priorities List: NPL Site Summary Reports. Volume 3 (Kerr-McGee Chemical Corp. (Soda Springs Plant) to Ormet Corp). Draft report (Final)

    SciTech Connect

    Houseman, V.

    1991-06-21

    Volume III of the Mining Sites on the National Priorities List contains the following NPL Site Summary Reports: Kerr-McGee Chemical Corp. (Soda Springs Plant), Lincoln Park, Martin Marietta Reduction Facility, Midvale Slag (Valley Materials Slag), Milltown Reservoir Sediments, Monsanto Chemical Company, Monticello Mill Site, Monticello Vicinity Properties, Mouat Industries, and Ormet Corporation.

  3. Evapotranspiration Cover for the 92-Acre Area Retired Mixed Waste Pits, Area 5 Waste Management Division, Nevada National Security Site, Final CQA Report

    SciTech Connect

    NSTec Environmental Management; The Delphi Groupe, Inc.; J. A. Cesare and Associates, Inc.

    2012-01-31

    The report is the Final Construction Quality Assurance (CQA) Report for the 92-Acrew Evapotranspiration Cover, Area 5 Waste Management Division Retired Mixed Waste Pits, Nevada National Security Site, Nevada, for the period of January 20, 2011, to January 31, 2012 The Area 5 RWMS uses engineered shallow-land burial cells to dispose of packaged waste. The 92-Acre Area encompasses the southern portion of the Area 5 RWMS, which has been designated for the first final closure operations. This area contains 13 Greater Confinement Disposal (GCD) boreholes, 16 narrow trenches, and 9 broader pits. With the exception of two active pits (P03 and P06), all trenches and pits in the 92-Acre Area had operational covers approximately 2.4 meters thick, at a minimum, in most areas when this project began. The units within the 92-Acre Area are grouped into the following six informal categories based on physical location, waste types and regulatory requirements: (1) Pit 3 Mixed Waste Disposal Unit (MWDU); (2) Corrective Action Unit (CAU) 111; (3) CAU 207; (4) Low-level waste disposal units; (5) Asbestiform low-level waste disposal units; and (6) One transuranic (TRU) waste trench.

  4. Nuclear Site Security in the Event of Terrorist Activity

    SciTech Connect

    Thomson, M.L.; Sims, J.

    2008-07-01

    This paper, presented as a poster, identifies why ballistic protection should now be considered at nuclear sites to counter terrorist threats. A proven and flexible form of multi purpose protection is described in detail with identification of trial results that show its suitability for this role. (authors)

  5. Revealing the nature of the active site on the carbon catalyst for C-H bond activation.

    PubMed

    Sun, XiaoYing; Li, Bo; Su, Dangsheng

    2014-09-28

    A reactivity descriptor for the C-H bond activation on the nanostructured carbon catalyst is proposed. Furthermore the calculations reveal that the single ketone group can be an active site in ODH reaction.

  6. Cellular Active N-Hydroxyurea FEN1 Inhibitors Block Substrate Entry to the Active Site

    PubMed Central

    Exell, Jack C.; Thompson, Mark J.; Finger, L. David; Shaw, Steven J.; Debreczeni, Judit; Ward, Thomas A.; McWhirter, Claire; Siöberg, Catrine L. B.; Martinez Molina, Daniel; Mark Abbott, W.; Jones, Clifford D.; Nissink, J. Willem M.; Durant, Stephen T.; Grasby, Jane A.

    2016-01-01

    The structure-specific nuclease human flap endonuclease-1 (hFEN1) plays a key role in DNA replication and repair and may be of interest as an oncology target. We present the first crystal structure of inhibitor-bound hFEN1 and show a cyclic N-hydroxyurea bound in the active site coordinated to two magnesium ions. Three such compounds had similar IC50 values but differed subtly in mode of action. One had comparable affinity for protein and protein–substrate complex and prevented reaction by binding to active site catalytic metal ions, blocking the unpairing of substrate DNA necessary for reaction. Other compounds were more competitive with substrate. Cellular thermal shift data showed engagement of both inhibitor types with hFEN1 in cells with activation of the DNA damage response evident upon treatment. However, cellular EC50s were significantly higher than in vitro inhibition constants and the implications of this for exploitation of hFEN1 as a drug target are discussed. PMID:27526030

  7. Active Layer and Moisture Measurements for Intensive Site 0 and 1, Barrow, Alaska

    DOE Data Explorer

    John Peterson

    2015-04-17

    These are measurements of Active Layer Thickness collected along several lines beginning in September, 2011 to the present. The data were collected at several time periods along the Site0 L2 Line, the Site1 AB Line, and an ERT Monitoring Line near Area A in Site1.

  8. Identification of promiscuous ene-reductase activity by mining structural databases using active site constellations

    PubMed Central

    Steinkellner, Georg; Gruber, Christian C.; Pavkov-Keller, Tea; Binter, Alexandra; Steiner, Kerstin; Winkler, Christoph; Łyskowski, Andrzej; Schwamberger, Orsolya; Oberer, Monika; Schwab, Helmut; Faber, Kurt; Macheroux, Peter; Gruber, Karl

    2014-01-01

    The exploitation of catalytic promiscuity and the application of de novo design have recently opened the access to novel, non-natural enzymatic activities. Here we describe a structural bioinformatic method for predicting catalytic activities of enzymes based on three-dimensional constellations of functional groups in active sites (‘catalophores’). As a proof-of-concept we identify two enzymes with predicted promiscuous ene-reductase activity (reduction of activated C–C double bonds) and compare them with known ene-reductases, that is, members of the Old Yellow Enzyme family. Despite completely different amino acid sequences, overall structures and protein folds, high-resolution crystal structures reveal equivalent binding modes of typical Old Yellow Enzyme substrates and ligands. Biochemical and biocatalytic data show that the two enzymes indeed possess ene-reductase activity and reveal an inverted stereopreference compared with Old Yellow Enzymes for some substrates. This method could thus be a tool for the identification of viable starting points for the development and engineering of novel biocatalysts. PMID:24954722

  9. Effects of protein flexibility and active site water molecules on the prediction of sites of metabolism for cytochrome P450 2C19 substrates.

    PubMed

    Li, Junhao; Cai, Jinya; Su, Haixia; Du, Hanwen; Zhang, Juan; Ding, Shihui; Liu, Guixia; Tang, Yun; Li, Weihua

    2016-03-01

    Structure-based prediction of sites of metabolism (SOMs) mediated by cytochrome P450s (CYPs) is of great interest in drug discovery and development. However, protein flexibility and active site water molecules remain a challenge for accurate SOM prediction. CYP2C19 is one of the major drug-metabolizing enzymes and has attracted considerable attention because of its polymorphism and capability of metabolizing ∼7% clinically used drugs. In this study, we systematically evaluated the effects of protein flexibility and active site water molecules on SOM prediction for CYP2C19 substrates. Multiple conformational sampling techniques including GOLD flexible residues sampling, molecular dynamics (MD) and tCONCOORD side-chain sampling were adopted for assessing the influence of protein flexibility on SOM prediction. The prediction accuracy could be significantly improved when protein flexibility was considered using the tCONCOORD sampling method, which indicated that the side-chain conformation was important for accurate prediction. However, the inclusion of the crystallographic or MD-derived water molecule(s) does not necessarily improve the prediction accuracy. Finally, a combination of docking results with SMARTCyp was found to be able to increase the SOM prediction accuracy.

  10. Are nest sites actively chosen? Testing a common assumption for three non-resource limited birds

    NASA Astrophysics Data System (ADS)

    Goodenough, A. E.; Elliot, S. L.; Hart, A. G.

    2009-09-01

    Many widely-accepted ecological concepts are simplified assumptions about complex situations that remain largely untested. One example is the assumption that nest-building species choose nest sites actively when they are not resource limited. This assumption has seen little direct empirical testing: most studies on nest-site selection simply assume that sites are chosen actively (and seek explanations for such behaviour) without considering that sites may be selected randomly. We used 15 years of data from a nestbox scheme in the UK to test the assumption of active nest-site choice in three cavity-nesting bird species that differ in breeding and migratory strategy: blue tit ( Cyanistes caeruleus), great tit ( Parus major) and pied flycatcher ( Ficedula hypoleuca). Nest-site selection was non-random (implying active nest-site choice) for blue and great tits, but not for pied flycatchers. We also considered the relative importance of year-specific and site-specific factors in determining occupation of nest sites. Site-specific factors were more important than year-specific factors for the tit species, while the reverse was true for pied flycatchers. Our results show that nest-site selection, in birds at least, is not always the result of active choice, such that choice should not be assumed automatically in studies of nesting behaviour. We use this example to highlight the need to test key ecological assumptions empirically, and the importance of doing so across taxa rather than for single "model" species.

  11. Final annual site environmental report, calendar year 1997, for the Laboratory for Energy-Related Health Research (LEHR), University of California at Davis, California

    SciTech Connect

    1998-09-01

    This Annual Site Environmental Report (ASER) describes DOE activities for the Environmental Restoration/Waste Management (ER/WM) Project at the Laboratory for Energy-Related Health Research (LEHR) site at UC Davis California. The report provides information about the Site and its environmental monitoring operation throughout calendar year 1997 for both radiological and non-radiological parameters. This report also describes activities conducted during 1997 in support of the Site environmental restoration efforts, and information about the impact of these activities on the public and the environment.

  12. Early Site Permit Demonstration Program: Recommendations for communication activities and public participation in the Early Site Permit Demonstration Program

    SciTech Connect

    Not Available

    1993-01-27

    On October 24, 1992, President Bush signed into law the National Energy Policy Act of 1992. The bill is a sweeping, comprehensive overhaul of the Nation`s energy laws, the first in more than a decade. Among other provisions, the National Energy Policy Act reforms the licensing process for new nuclear power plants by adopting a new approach developed by the US Nuclear Regulatory Commission (NRC) in 1989, and upheld in court in 1992. The NRC 10 CFR Part 52 rule is a three-step process that guarantees public participation at each step. The steps are: early site permit approval; standard design certifications; and, combined construction/operating licenses for nuclear power reactors. Licensing reform increases an organization`s ability to respond to future baseload electricity generation needs with less financial risk for ratepayers and the organization. Costly delays can be avoided because design, safety and siting issues will be resolved before a company starts to build a plant. Specifically, early site permit approval allows for site suitability and acceptability issues to be addressed prior to an organization`s commitment to build a plant. Responsibility for site-specific activities, including communications and public participation, rests with those organizations selected to try out early site approval. This plan has been prepared to assist those companies (referred to as sponsoring organizations) in planning their communications and public involvement programs. It provides research findings, information and recommendations to be used by organizations as a resource and starting point in developing their own plans.

  13. Structural characterization of single nucleotide variants at ligand binding sites and enzyme active sites of human proteins

    PubMed Central

    Yamada, Kazunori D.; Nishi, Hafumi; Nakata, Junichi; Kinoshita, Kengo

    2016-01-01

    Functional sites on proteins play an important role in various molecular interactions and reactions between proteins and other molecules. Thus, mutations in functional sites can severely affect the overall phenotype. Progress of genome sequencing projects has yielded a wealth of information on single nucleotide variants (SNVs), especially those with less than 1% minor allele frequency (rare variants). To understand the functional influence of genetic variants at a protein level, we investigated the relationship between SNVs and protein functional sites in terms of minor allele frequency and the structural position of variants. As a result, we observed that SNVs were less abundant at ligand binding sites, which is consistent with a previous study on SNVs and protein interaction sites. Additionally, we found that non-rare variants tended to be located slightly apart from enzyme active sites. Examination of non-rare variants revealed that most of the mutations resulted in moderate changes of the physico-chemical properties of amino acids, suggesting the existence of functional constraints. In conclusion, this study shows that the mapping of genetic variants on protein structures could be a powerful approach to evaluate the functional impact of rare genetic variations. PMID:27924270

  14. Lamellipodial actin mechanically links myosin activity with adhesion site formation

    PubMed Central

    Giannone, Gregory; Dubin-Thaler, Benjamin; Rossier, Olivier; Cai, Yunfei; Chaga, Oleg; Jiang, Guoying; Beaver, William; Döbereiner, Hans-Günther; Freund, Yoav; Borisy, Gary; Sheetz, Michael P.

    2013-01-01

    Summary Cell motility proceeds by cycles of edge protrusion, adhesion and retraction. Whether these functions are coordinated by biochemical or biomechanical processes is unknown. We find that myosin II pulls the rear of the lamellipodial actin network, causing upward bending, edge retraction and initiation of new adhesion sites. The network then separates from the edge and condenses over the myosin. Protrusion resumes as lamellipodial actin regenerates from the front and extends rearward until it reaches newly assembled myosin, initiating the next cycle. Upward bending, observed by evanescence and electron microscopy, results in ruffle formation when adhesion strength is low. Correlative fluorescence and electron microscopy shows that the regenerating lamellipodium forms a cohesive, separable layer of actin above the lamellum. Thus, actin polymerization periodically builds a mechanical link, the lamellipodium, connecting myosin motors with the initiation of adhesion sites, suggesting that the major functions driving motility are coordinated by a biomechanical process. PMID:17289574

  15. Stereospecific suppression of active site mutants by methylphosphonate substituted substrates reveals the stereochemical course of site-specific DNA recombination.

    PubMed

    Rowley, Paul A; Kachroo, Aashiq H; Ma, Chien-Hui; Maciaszek, Anna D; Guga, Piotr; Jayaram, Makkuni

    2015-07-13

    Tyrosine site-specific recombinases, which promote one class of biologically important phosphoryl transfer reactions in DNA, exemplify active site mechanisms for stabilizing the phosphate transition state. A highly conserved arginine duo (Arg-I; Arg-II) of the recombinase active site plays a crucial role in this function. Cre and Flp recombinase mutants lacking either arginine can be rescued by compensatory charge neutralization of the scissile phosphate via methylphosphonate (MeP) modification. The chemical chirality of MeP, in conjunction with mutant recombinases, reveals the stereochemical contributions of Arg-I and Arg-II. The SP preference of the native reaction is specified primarily by Arg-I. MeP reaction supported by Arg-II is nearly bias-free or RP-biased, depending on the Arg-I substituent. Positional conservation of the arginines does not translate into strict functional conservation. Charge reversal by glutamic acid substitution at Arg-I or Arg-II has opposite effects on Cre and Flp in MeP reactions. In Flp, the base immediately 5' to the scissile MeP strongly influences the choice between the catalytic tyrosine and water as the nucleophile for strand scission, thus between productive recombination and futile hydrolysis. The recombinase active site embodies the evolutionary optimization of interactions that not only favor the normal reaction but also proscribe antithetical side reactions.

  16. Active-Site Hydration and Water Diffusion in Cytochrome P450cam: A Highly Dynamic Process

    SciTech Connect

    Miao, Yinglong; Baudry, Jerome Y

    2011-01-01

    Long-timescale molecular dynamics simulations (300 ns) are performed on both the apo- (i.e., camphor-free) and camphor-bound cytochrome P450cam (CYP101). Water diffusion into and out of the protein active site is observed without biased sampling methods. During the course of the molecular dynamics simulation, an average of 6.4 water molecules is observed in the camphor-binding site of the apo form, compared to zero water molecules in the binding site of the substrate-bound form, in agreement with the number of water molecules observed in crystal structures of the same species. However, as many as 12 water molecules can be present at a given time in the camphor-binding region of the active site in the case of apo-P450cam, revealing a highly dynamic process for hydration of the protein active site, with water molecules exchanging rapidly with the bulk solvent. Water molecules are also found to exchange locations frequently inside the active site, preferentially clustering in regions surrounding the water molecules observed in the crystal structure. Potential-of-mean-force calculations identify thermodynamically favored trans-protein pathways for the diffusion of water molecules between the protein active site and the bulk solvent. Binding of camphor in the active site modifies the free-energy landscape of P450cam channels toward favoring the diffusion of water molecules out of the protein active site.

  17. Remedial action and site design for stabilization of the inactive uranium mill tailings sites at Slick Rock, Colorado. Attachment 2, Geology report: Appendix B, Preliminary final

    SciTech Connect

    Not Available

    1994-03-01

    Detailed investigations of geologic, geomorphic, and seismic conditions at the Burro Canyon site were conducted by the US Department of Energy (DOE) as a disposal site for the tailings at two processing sites near the Slick Rock, Colorado, post office. The purposes of these studies are basic site characterization and identification of potential geologic hazards that could affect long-term site stability. Subsequent engineering studies (e.g., analyses of hydrologic and liquefaction hazards) used the data developed in these studies. The geomorphic analysis was employed in the design of effective erosion protection. Studies of the regional and local seismotectonic setting, which included a detailed search for possible capable faults within a 65-km radius of the site, provided the basis for seismic design parameters.

  18. Structural mechanism of RuBisCO activation by carbamylation of the active site lysine.

    PubMed

    Stec, Boguslaw

    2012-11-13

    Ribulose 1,5-bisphosphate carboxylase/oxygenase (RuBisCO) is a crucial enzyme in carbon fixation and the most abundant protein on earth. It has been studied extensively by biochemical and structural methods; however, the most essential activation step has not yet been described. Here, we describe the mechanistic details of Lys carbamylation that leads to RuBisCO activation by atmospheric CO(2). We report two crystal structures of nitrosylated RuBisCO from the red algae Galdieria sulphuraria with O(2) and CO(2) bound at the active site. G. sulphuraria RuBisCO is inhibited by cysteine nitrosylation that results in trapping of these gaseous ligands. The structure with CO(2) defines an elusive, preactivation complex that contains a metal cation Mg(2+) surrounded by three H(2)O/OH molecules. Both structures suggest the mechanism for discriminating gaseous ligands by their quadrupole electric moments. We describe conformational changes that allow for intermittent binding of the metal ion required for activation. On the basis of these structures we propose the individual steps of the activation mechanism. Knowledge of all these elements is indispensable for engineering RuBisCO into a more efficient enzyme for crop enhancement or as a remedy to global warming.

  19. Silver-Coated Nylon Dressing Plus Active DC Microcurrent for Healing of Autogenous Skin Donor Sites

    DTIC Science & Technology

    2013-08-01

    Silver-Coated Nylon Dressing Plus Active DC Microcurrent for Healing of Autogenous Skin Donor Sites Edward W. Malin, MD, Chaya M. Galin, BSN, RN... microcurrent in comparison to silver-coated dressing with sham microcurrent on wound-closure time for autogenous skin donor sites. Methods: Four...hundred five patients were screened for treatment of their donor sites using a silver-coated nylon dressing with either sham or active microcurrent

  20. 76 FR 30696 - Reimbursement for Costs of Remedial Action at Active Uranium and Thorium Processing Sites

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-26

    ... Reimbursement for Costs of Remedial Action at Active Uranium and Thorium Processing Sites AGENCY: Department of... eligible active uranium and thorium processing site licensees for reimbursement under Title X of the Energy... requires DOE to reimburse eligible uranium and thorium licensees for certain costs of...

  1. 76 FR 24871 - Reimbursement for Costs of Remedial Action at Active Uranium and Thorium Processing Sites

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-05-03

    ... Reimbursement for Costs of Remedial Action at Active Uranium and Thorium Processing Sites AGENCY: Department of... from eligible active uranium and thorium processing site licensees for reimbursement under Title X of...). Title X requires DOE to reimburse eligible uranium and thorium licensees for certain costs...

  2. Final Characterization Report for Corrective Action Unit 109: Area 2 U-2BU Crater, Nevada Test Site, Nevada, Revision 1

    SciTech Connect

    ITLV

    1998-12-01

    Corrective Action Unit 109, Area 2 U-2bu Crater, is an inactive Resource Conservation and Recovery Act Part A Permit disposal unit located in Area 2 at the Nevada Test Site, Nevada. The Corrective Action Unit has been characterized under the requirements of the Nevada Test Site Resource Conservation and Recovery Act, Part A Permit (NDEP, 1995) and Title 40 Code of Federal Regulations Part 265 (CFR, 1996). The site characterization was performed under the RCRA Part A Permit Characterization Plan for the U-2bu Subsidence Crater (DOE/NV, 1998c), as approved by the Nevada Division of Environmental Protection (Liebendorfer, 1998). The primary objective of the site characterization activities was to evaluate the presence, concentration, and extent of any Resource Conservation and Recovery Act contaminants in the crater. Surface soil samples were collected on April 22, 1998, and subsurface soil samples and geotechnical samples were collected from April 27-29, 1998. Soil samples were collected using a hand auger or a piston-type drive hammer to advance a 5-centimeter (2-inch) diameter steel sampling tool into the ground. The permit for the Nevada Test Site requires that Corrective Action Unit 109 be closed under 40 Code of Federal Regulations 265 Subpart G and 40 Code of Federal Regulations Part 265.310 (CFR, 1996). Analysis of the data collected during the characterization effort indicates that lead was detected in Study Area 1 at 5.7 milligrams per liter, above the regulatory level in 40 Code of Federal Regulations 261.24 of 5.0 milligrams per liter. Except for the lead detection at a single location within the crater, the original Resource Conservation Recovery Act constituents of potential concern determined between the U.S. Department of Energy, Nevada Operations Office and the Nevada Department of Environmental Protection during the Data Quality Objectives process (DOE/NV, 1998b) were not found to be present at Corrective Action Unit 109 above regulatory levels of

  3. Designing a Highly Active Metal-Free Oxygen Reduction Catalyst in Membrane Electrode Assemblies for Alkaline Fuel Cells: Effects of Pore Size and Doping-Site Position.

    PubMed

    Lee, Seonggyu; Choun, Myounghoon; Ye, Youngjin; Lee, Jaeyoung; Mun, Yeongdong; Kang, Eunae; Hwang, Jongkook; Lee, Young-Ho; Shin, Chae-Ho; Moon, Seung-Hyeon; Kim, Soo-Kil; Lee, Eunsung; Lee, Jinwoo

    2015-08-03

    To promote the oxygen reduction reaction of metal-free catalysts, the introduction of porous structure is considered as a desirable approach because the structure can enhance mass transport and host many catalytic active sites. However, most of the previous studies reported only half-cell characterization; therefore, studies on membrane electrode assembly (MEA) are still insufficient. Furthermore, the effect of doping-site position in the structure has not been investigated. Here, we report the synthesis of highly active metal-free catalysts in MEAs by controlling pore size and doping-site position. Both influence the accessibility of reactants to doping sites, which affects utilization of doping sites and mass-transport properties. Finally, an N,P-codoped ordered mesoporous carbon with a large pore size and precisely controlled doping-site position showed a remarkable on-set potential and produced 70% of the maximum power density obtained using Pt/C.

  4. A model of the rabies virus glycoprotein active site.

    PubMed

    Rustici, M; Bracci, L; Lozzi, L; Neri, P; Santucci, A; Soldani, P; Spreafico, A; Niccolai, N

    1993-06-01

    The glycoprotein from the neurotropic rabies virus shows a significant homology with the alpha neurotoxin that binds to the nicotinic acetylcholine receptor. The crystal structure of the alpha neurotoxins suggests that the Arg 37 guanidinium group and the Asp 31 side-chain carboxylate of the erabutoxin have stereochemical features resembling those of acetylcholine. Conformational studies on the Asn194-Ser195-Arg196-Gly197 tetrapeptide, an essential part of the binding site of the rabies virus glycoprotein, indicate that the side chains of Asn and Arg could also mimic the acetylcholine structure. This observation is consistent with the recently proposed mechanism of the viral infection.

  5. Spectroscopic insights into the nature of active sites in iron–nitrogen–carbon electrocatalysts for oxygen reduction in acid

    SciTech Connect

    Jia, Qingying; Ramaswamy, Nagappan; Tylus, Urszula; Strickland, Kara; Li, Jingkun; Serov, Alexey; Artyushkova, Kateryna; Atanassov, Plamen; Anibal, Jacob; Gumeci, Cenk; Barton, Scott Calabrese; Sougrati, Moulay-Tahar; Jaouen, Frederic; Halevi, Barr; Mukerjee, Sanjeev

    2016-11-01

    Developing efficient and inexpensive catalysts for the sluggish oxygen reduction reaction (ORR) constitutes one of the grand challenges in the fabrication of commercially viable fuel cell devices and metal–air batteries for future energy applications. Despite recent achievements in designing advanced Pt-based and Pt-free catalysts, current progress primarily involves an empirical approach of trial-and-error combination of precursors and synthesis conditions, which limits further progress. Rational design of catalyst materials requires proper understanding of the mechanistic origin of the ORR and the underlying surface properties under operating conditions that govern catalytic activity. Herein, several different groups of iron-based catalysts synthesized via different methods and/or precursors were systematically studied by combining multiple spectroscopic techniques under ex situ and in situ conditions in an effort to obtain a comprehensive understanding of the synthesis-products correlations, nature of active sites, and the reaction mechanisms. These catalysts include original macrocycles, macrocycle-pyrolyzed catalysts, and Fe-N–C catalysts synthesized from individual Fe, N, and C precursors including polymer-based catalysts, metal organic framework (MOF)-based catalysts, and sacrificial support method (SSM)-based catalysts. The latter group of catalysts is most promising as not only they exhibit exceptional ORR activity and/or durability, but also the final products are controllable. We show that the high activity observed for most pyrolyzed Fe-based catalysts can mainly be attributed to a single active site: non-planar Fe–N4 moiety embedded in distorted carbon matrix characterized by a high potential for the Fe2+/3+ redox transition in acidic electrolyte/environment. The high intrinsic ORR activity, or turnover frequency (TOF), of this site is shown to be accounted for by redox catalysis mechanism that highlights the dominant role

  6. Proteome-wide analysis of nonsynonymous single-nucleotide variations in active sites of human proteins.

    PubMed

    Dingerdissen, Hayley; Motwani, Mona; Karagiannis, Konstantinos; Simonyan, Vahan; Mazumder, Raja

    2013-03-01

    An enzyme's active site is essential to normal protein activity such that any disruptions at this site may lead to dysfunction and disease. Nonsynonymous single-nucleotide variations (nsSNVs), which alter the amino acid sequence, are one type of disruption that can alter the active site. When this occurs, it is assumed that enzyme activity will vary because of the criticality of the site to normal protein function. We integrate nsSNV data and active site annotations from curated resources to identify all active-site-impacting nsSNVs in the human genome and search for all pathways observed to be associated with this data set to assess the likely consequences. We find that there are 934 unique nsSNVs that occur at the active sites of 559 proteins. Analysis of the nsSNV data shows an over-representation of arginine and an under-representation of cysteine, phenylalanine and tyrosine when comparing the list of nsSNV-impacted active site residues with the list of all possible proteomic active site residues, implying a potential bias for or against variation of these residues at the active site. Clustering analysis shows an abundance of hydrolases and transferases. Pathway and functional analysis shows several pathways over- or under-represented in the data set, with the most significantly affected pathways involved in carbohydrate metabolism. We provide a table of 32 variation-substrate/product pairs that can be used in targeted metabolomics experiments to assay the effects of specific variations. In addition, we report the significant prevalence of aspartic acid to histidine variation in eight proteins associated with nine diseases including glycogen storage diseases, lacrimo-auriculo-dento-digital syndrome, Parkinson's disease and several cancers.

  7. 75 FR 27557 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-17

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB Review and Comments Request. Form Title: Application for... affects entities involved in the export of U.S. goods and services. Annual Number of Respondents:...

  8. 75 FR 73082 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-29

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB Review and Comments Request. Form Title: Application for..., collect, and if needed, restructure international loans. This application will also improve Ex- Im Bank'...

  9. 75 FR 27556 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-05-17

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB Review and Comments Request. Form Title: Report of Premiums... in the export of U.S. goods and services. Annual Number of Respondents: 150. Estimated Time...

  10. 76 FR 19356 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-04-07

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB review and comments request. Form Title: Letter of Interest... Review: Regular. Need and Use: Ex-Im Bank's Letter of Interest (LI) is a pre-export tool to help...

  11. 77 FR 284 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-04

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB review and comments request. Form Title: Co-Financing with... proposed co-financing transaction between a U.S. exporter, Ex-Im Bank, and a foreign export credit...

  12. 75 FR 8352 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB review and comments request. FORM TITLE: Report of Premiums.... Affected Public: This form affects entities involved in the export of U.S. goods and services....

  13. 76 FR 65725 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-24

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB review and comments request. Form Title: Used Equipment... Export-Import Bank's determination of the appropriate term for the transaction. The form can be view...

  14. 75 FR 8353 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-02-24

    ... U.S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB Review and Comments Request. Form Title: Application... export of U.S. goods and services. Annual Number of Respondents: 84. Estimated Time Per Respondent:...

  15. 77 FR 284 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-01-04

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB Review and Comments Request. Form Title: Used Equipment... Export-Import Bank's determination of the appropriate term for the transaction. The form can be viewed...

  16. 77 FR 56207 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2012-09-12

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB Review and Comments Request. Form Title: Application for... prohibits Ex-Im Bank's Board of Directors from approving ``any transaction in which a person that is...

  17. 76 FR 64944 - Agency Information Collection Activities: Final Collection; Comment Request

    Federal Register 2010, 2011, 2012, 2013, 2014

    2011-10-19

    ....S. Agency Information Collection Activities: Final Collection; Comment Request AGENCY: Export-Import Bank of the U.S. ACTION: Submission for OMB review and comments request. Form Title: Co-Financing with... proposed co-financing transaction between a U.S. exporter, Ex-Im Bank, and a foreign export credit...

  18. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Durango, Colorado: Attachment 2, Geology report. Revised final report

    SciTech Connect

    Not Available

    1991-12-01

    Detailed investigations of geologic, geomorphic, and seismic conditions at the Bodo Canyon disposal site were conducted. The purpose of these investigations was basic site characterization and identification of potential geologic hazards that could affect long-term site stability. Subsequent engineering studies, such as analyses of hydrologic and liquefaction hazards, used the data developed in these studies. The geomorphic analysis was employed in the design of effective erosion protection. Studies of the regional and local seismotectonic setting, which included a detailed search for possible capable faults within a 65 kilometer radius of the site, provided the basis for seismic design parameters. The scope of work performed included the following: Compilation and analysis of previous published and unpublished geologic literature and maps; Review of historical and instrumental earthquake data; Review of site-specific subsurface geologic data, including lithologic and geophysical logs of exploratory boreholes advanced in the site area; Photogeologic interpretations of existing conventional aerial photographs; and, Ground reconnaissance and mapping of the site region.

  19. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Gunnison, Colorado. Attachment 2, Geology report: Final report

    SciTech Connect

    Not Available

    1992-10-01

    Detailed investigations of geologic, geomorphic, and seismic conditions at the Landfill disposal site were conducted. The purpose of these studies was basic site characterization and identification of potential geologic hazards that could affect long-term site stability. Subsequent engineering studies, such as analyses of hydrologic and liquefaction hazards, used the data developed in these studies. The geomorphic analysis was employed in the design of effective erosion protection. Studies of the regional and local seismotectonic setting, which included a detailed search for possible capable faults within a 65-kilometer (km) (40-mile) radius of the site, provided the basis for seismic design parameters. The scope of work performed included the following: Compilation and analysis of previous published and unpublished geologic literature and maps. Review of historical and instrumental earthquake data. Review of site-specific subsurface geologic data, including lithologic and geophysical logs of exploratory boreholes advanced in the site area. Photogeologic interpretations of existing conventional aerial photographs. Ground reconnaissance and mapping of the site region.

  20. Characterization of the active site topography of manganese peroxidase using mechanism based inhibitors

    SciTech Connect

    Harris, R.; Wartishi, H.; Gold. M.; de Montellano, P.O. Oregon Graduate Inst. of Science and Technology, Beaverton )

    1991-03-11

    Manganese peroxidase (MnP), extracellular heme enzyme from the lignin-degrading fungus Phanerochaete chrysosporium, normally oxidizes Mn(II) to Mn(III). MnP is rapidly and completely inactivated in a H{sub 2}O{sub 2}-dependent reaction by 2 equivalents of sodium azide. The inactivation is paralleled by formation of azidyl radicals and high yield conversion of the prosthetic heme into a mexo-azido adduct. The meso-azido enzyme is oxidized by H{sub 2}O{sub 2} to a Compound II-like species. MnP is also inactivated by phenyl-, methyl- and ethylhydrazine. The phenylhydrazine reaction is too rapid for kinetic analysis, but K{sub I} = 402 mM and k{sub inact} = 0.22 min{sup {minus}1} for the inactivation by methylhydrazine. Reaction with phenylhydrazine at pH 4.5 does not yield iron-phenyl, N-phenyl, or meso-phenyl heme adducts. Ethylhydrazine inactivates the enzyme both at pH 4.5 and 7.0 but a {delta}-meso-ethylheme product is detected only at pH 7.0. Reconstitution of apo-MnP with {delta}-meso-ethylheme yields enzyme still capable of forming a Compound II-like species yet having diminished catalytic activity. Finally, Co(II) inhibits the enzyme competitively with respect to Mn(II) but does not inhibit its inactivation by azide or the alkylhydrazines. The results argue that substrates interact with the heme edge in the vicinity of the {delta}-meso carbon. They also suggest that Mn(II) and Co(II) bind to a common site close to the {delta}-meso carbon without blocking the approach of small molecules to the heme edge. An active site model is proposed that accommodates these results.

  1. Assessment of activation products in the Savannah River Site environment

    SciTech Connect

    Carlton, W.H.; Denham, M.

    1996-07-01

    This document assesses the impact of radioactive activation products released from SRS facilities since the first reactor became operational late in 1953. The isotopes reported here are those whose release resulted in the highest dose to people living near SRS: {sup 32}P, {sup 51}Cr, {sup 60}C, and {sup 65}Zn. Release pathways, emission control features, and annual releases to the aqueous and atmospheric environments are discussed. No single incident has resulted in a major acute release of activation products to the environment. The releases were the result of normal operations of the reactors and separations facilities. Releases declined over the years as better controls were established and production was reduced. The overall radiological impact of SRS activation product atmospheric releases from 1954 through 1994 on the offsite maximally exposed individual can be characterized by a total dose of 0.76 mrem. During the same period, such an individual received a total dose of 14,400 mrem from non-SRS sources of ionizing radiation present in the environment. SRS activation product aqueous releases between 1954 and 1994 resulted in a total dose of 54 mrem to the offsite maximally exposed individual. The impact of SRS activation product releases on offsite populations also has been evaluated.

  2. Synthetic models of the active site of catechol oxidase: mechanistic studies.

    PubMed

    Koval, Iryna A; Gamez, Patrick; Belle, Catherine; Selmeczi, Katalin; Reedijk, Jan

    2006-09-01

    The ability of copper proteins to process dioxygen at ambient conditions has inspired numerous research groups to study their structural, spectroscopic and catalytic properties. Catechol oxidase is a type-3 copper enzyme usually encountered in plant tissues and in some insects and crustaceans. It catalyzes the conversion of a large number of catechols into the respective o-benzoquinones, which subsequently auto-polymerize, resulting in the formation of melanin, a dark pigment thought to protect a damaged tissue from pathogens. After the report of the X-ray crystal structure of catechol oxidase a few years earlier, a large number of publications devoted to the biomimetic modeling of its active site appeared in the literature. This critical review (citing 114 references) extensively discusses the synthetic models of this enzyme, with a particular emphasis on the different approaches used in the literature to study the mechanism of the catalytic oxidation of the substrate (catechol) by these compounds. These are the studies on the substrate binding to the model complexes, the structure-activity relationship, the kinetic studies of the catalytic oxidation of the substrate and finally the substrate interaction with (per)oxo-dicopper adducts. The general overview of the recognized types of copper proteins and the detailed description of the crystal structure of catechol oxidase, as well as the proposed mechanisms of the enzymatic cycle are also presented.

  3. A Tale of Two Emergences: Sunrise II Observations of Emergence Sites in a Solar Active Region

    NASA Astrophysics Data System (ADS)

    Centeno, R.; Blanco Rodríguez, J.; Del Toro Iniesta, J. C.; Solanki, S. K.; Barthol, P.; Gandorfer, A.; Gizon, L.; Hirzberger, J.; Riethmüller, T. L.; van Noort, M.; Orozco Suárez, D.; Berkefeld, T.; Schmidt, W.; Martínez Pillet, V.; Knölker, M.

    2017-03-01

    In 2013 June, the two scientific instruments on board the second Sunrise mission witnessed, in detail, a small-scale magnetic flux emergence event as part of the birth of an active region. The Imaging Magnetograph Experiment (IMaX) recorded two small (∼ 5\\prime\\prime ) emerging flux patches in the polarized filtergrams of a photospheric Fe i spectral line. Meanwhile, the Sunrise Filter Imager (SuFI) captured the highly dynamic chromospheric response to the magnetic fields pushing their way through the lower solar atmosphere. The serendipitous capture of this event offers a closer look at the inner workings of active region emergence sites. In particular, it reveals in meticulous detail how the rising magnetic fields interact with the granulation as they push through the Sun’s surface, dragging photospheric plasma in their upward travel. The plasma that is burdening the rising field slides along the field lines, creating fast downflowing channels at the footpoints. The weight of this material anchors this field to the surface at semi-regular spatial intervals, shaping it in an undulatory fashion. Finally, magnetic reconnection enables the field to release itself from its photospheric anchors, allowing it to continue its voyage up to higher layers. This process releases energy that lights up the arch-filament systems and heats the surrounding chromosphere.

  4. Final work plan : targeted groundwater sampling and monitoring well installation for potential site reclassification at Barnes, Kansas.

    SciTech Connect

    LaFreniere, L. M.

    2006-07-11

    This ''Work Plan'' outlines the scope of work for a targeted groundwater sampling investigation and monitoring well installation at Barnes, Kansas. This activity is being conducted at the request of the Kansas Department of Health and Environment (KDHE), in accordance with the intergovernmental agreement between the KDHE and the Commodity Credit Corporation (CCC), an agency of the U.S. Department of Agriculture (USDA). Data resulting from the proposed work will be used to determine the hydraulic gradient near the former CCC/USDA facility, delineate the downgradient carbon tetrachloride plume, and determine additional monitoring requirements at Barnes. The overall goal is to establish criteria for monitoring leading to potential site reclassification. The proposed work will be performed on behalf of the CCC/USDA by the Environmental Science Division of Argonne National Laboratory. Argonne is a nonprofit, multidisciplinary research center operated by the University of Chicago for the U.S. Department of Energy (DOE). The Farm Service Agency of the USDA has entered into an interagency agreement with DOE, under which Argonne provides technical assistance with environmental site characterization and remediation at former CCC/USDA grain storage facilities. Argonne issued a ''Master Work Plan'' (Argonne 2002) to provide general guidance for all investigations at former CCC/USDA facilities in Kansas. The ''Master Work Plan'', approved by the KDHE, contains the materials common to investigations at all locations in Kansas. This document must be consulted for the complete details of plans for this work associated with the former CCC/USDA facility at Barnes.

  5. All the catalytic active sites of MoS2 for hydrogen evolution

    DOE PAGES

    Li, Guoqing; Zhang, Du; Qiao, Qiao; ...

    2016-11-29

    MoS2 presents a promising low-cost catalyst for the hydrogen evolution reaction (HER), but the understanding about its active sites has remained limited. Here we present an unambiguous study of the catalytic activities of all possible reaction sites of MoS2, including edge sites, sulfur vacancies, and grain boundaries. We demonstrate that, in addition to the well-known catalytically active edge sites, sulfur vacancies provide another major active site for the HER, while the catalytic activity of grain boundaries is much weaker. Here, the intrinsic turnover frequencies (Tafel slopes) of the edge sites, sulfur vacancies, and grain boundaries are estimated to be 7.5more » s–1 (65–75 mV/dec), 3.2 s–1 (65–85 mV/dec), and 0.1 s–1 (120–160 mV/dec), respectively. We also demonstrate that the catalytic activity of sulfur vacancies strongly depends on the density of the vacancies and the local crystalline structure in proximity to the vacancies. Unlike edge sites, whose catalytic activity linearly depends on the length, sulfur vacancies show optimal catalytic activities when the vacancy density is in the range of 7–10%, and the number of sulfur vacancies in high crystalline quality MoS2 is higher than that in low crystalline quality MoS2, which may be related with the proximity of different local crystalline structures to the vacancies.« less

  6. Quantifying the density and utilization of active sites in non-precious metal oxygen electroreduction catalysts

    PubMed Central

    Sahraie, Nastaran Ranjbar; Kramm, Ulrike I.; Steinberg, Julian; Zhang, Yuanjian; Thomas, Arne; Reier, Tobias; Paraknowitsch, Jens-Peter; Strasser, Peter

    2015-01-01

    Carbon materials doped with transition metal and nitrogen are highly active, non-precious metal catalysts for the electrochemical conversion of molecular oxygen in fuel cells, metal air batteries, and electrolytic processes. However, accurate measurement of their intrinsic turn-over frequency and active-site density based on metal centres in bulk and surface has remained difficult to date, which has hampered a more rational catalyst design. Here we report a successful quantification of bulk and surface-based active-site density and associated turn-over frequency values of mono- and bimetallic Fe/N-doped carbons using a combination of chemisorption, desorption and 57Fe Mössbauer spectroscopy techniques. Our general approach yields an experimental descriptor for the intrinsic activity and the active-site utilization, aiding in the catalyst development process and enabling a previously unachieved level of understanding of reactivity trends owing to a deconvolution of site density and intrinsic activity. PMID:26486465

  7. Monitoring Soil Erosion of a Burn Site in the Central Basin and Range Ecoregion: Final Report on Measurements at the Gleason Fire Site, Nevada

    SciTech Connect

    Miller, Julianne; Etyemezian, Vicken; Shillito, Rose; Cablk, Mary; Fenstermaker, Lynn; Shafer, David

    2013-10-01

    The increase in wildfires in arid and semi-arid parts of Nevada and elsewhere in the southwestern United States has implications for post-closure management and long-term stewardship for Soil Corrective Action Units (CAUs) on the Nevada National Security Site (NNSS) for which the Nevada Field Office of the United States Department of Energy, National Nuclear Security Administration has responsibility. For many CAUs and Corrective Action Sites, where closure-in-place alternatives are now being implemented or considered, there is a chance that these sites could burn over at some time while they still pose a risk to the environment or human health, given the long half lives of some of the radionuclide contaminants. This study was initiated to examine the effects and duration of wildfire on wind and water erodibility on sites analogous to those that exist on the NNSS. The data analyzed herein were gathered at the prescribed Gleason Fire site near Ely, Nevada, a site comparable to the northern portion of the NNSS. Quantification of wind erosion was conducted with a Portable In-Situ Wind ERosion Lab (PI-SWERL) on unburned soils, and on interspace and plant understory soils within the burned area. The PI-SWERL was used to estimate emissions of suspendible particles (particulate matter with aerodynamic diameters less than or equal to 10 micrometers) at different wind speeds. Filter samples, collected from the exhaust of the PI-SWERL during measurements, were analyzed for chemical composition. Based on nearly three years of data, the Gleason Fire site does not appear to have returned to pre burn wind erosion levels. Chemical composition data of suspendible particles are variable and show a trend toward pre-burn levels, but provide little insight into how the composition has been changing over time since the fire. Soil, runoff, and sediment data were collected from the Gleason Fire site to monitor the water erosion potential over the nearly three-year period. Soil

  8. Marine Biology Field Trip Sites. Ocean Related Curriculum Activities.

    ERIC Educational Resources Information Center

    Pauls, John

    The ocean affects all of our lives. Therefore, awareness of and information about the interconnections between humans and oceans are prerequisites to making sound decisions for the future. Project ORCA (Ocean Related Curriculum Activities) has developed interdisciplinary curriculum materials designed to meet the needs of students and teachers…

  9. An active site mutation increases the polymerase activity of the guinea pig-lethal Marburg virus.

    PubMed

    Koehler, Alexander; Kolesnikova, Larissa; Becker, Stephan

    2016-10-01

    Marburg virus (MARV) causes severe, often fatal, disease in humans and transient illness in rodents. Sequential passaging of MARV in guinea pigs resulted in selection of a lethal virus containing 4 aa changes. A D184N mutation in VP40 (VP40D184N), which leads to a species-specific gain of viral fitness, and three mutations in the active site of viral RNA-dependent RNA polymerase L, which were investigated in the present study for functional significance in human and guinea pig cells. The transcription/replication activity of L mutants was strongly enhanced by a substitution at position 741 (S741C), and inhibited by other substitutions (D758A and A759D) in both species. The polymerase activity of L carrying the S741C substitution was eightfold higher in guinea pig cells than in human cells upon co-expression with VP40D184N, suggesting that the additive effect of the two mutations provides MARV a replicative advantage in the new host.

  10. Encroachment of Human Activity on Sea Turtle Nesting Sites

    NASA Astrophysics Data System (ADS)

    Ziskin, D.; Aubrecht, C.; Elvidge, C.; Tuttle, B.; Baugh, K.; Ghosh, T.

    2008-12-01

    The encroachment of anthropogenic lighting on sea turtle nesting sites poses a serious threat to the survival of these animals [Nicholas, 2001]. This danger is quantified by combining two established data sets. The first is the Nighttime Lights data produced by the NOAA National Geophysical Data Center [Elvidge et al., 1997]. The second is the Marine Turtle Database produced by the World Conservation Monitoring Centre (WCMC). The technique used to quantify the threat of encroachment is an adaptation of the method described in Aubrecht et al. [2008], which analyzes the stress on coral reef systems by proximity to nighttime lights near the shore. Nighttime lights near beaches have both a direct impact on turtle reproductive success since they disorient hatchlings when they mistake land-based lights for the sky-lit surf [Lorne and Salmon, 2007] and the lights are also a proxy for other anthropogenic threats. The identification of turtle nesting sites with high rates of encroachment will hopefully steer conservation efforts to mitigate their effects [Witherington, 1999]. Aubrecht, C, CD Elvidge, T Longcore, C Rich, J Safran, A Strong, M Eakin, KE Baugh, BT Tuttle, AT Howard, EH Erwin, 2008, A global inventory of coral reef stressors based on satellite observed nighttime lights, Geocarto International, London, England: Taylor and Francis. In press. Elvidge, CD, KE Baugh, EA Kihn, HW Kroehl, ER Davis, 1997, Mapping City Lights with Nighttime Data from the DMSP Operational Linescan System, Photogrammatic Engineering and Remote Sensing, 63:6, pp. 727-734. Lorne, JK, M Salmon, 2007, Effects of exposure to artificial lighting on orientation of hatchling sea turtles on the beach and in the ocean, Endangered Species Research, Vol. 3: 23-30. Nicholas, M, 2001, Light Pollution and Marine Turtle Hatchlings: The Straw that Breaks the Camel's Back?, George Wright Forum, 18:4, p77-82. Witherington, BE, 1999, Reducing Threats To Nesting Habitat, Research and Management Techniques for

  11. Remedial action plan and site design for stabilization of the inactive uranium mill tailings site at Lowman, Idaho: Remedial action selection report for the Lowman UMTRA project site, Idaho. Final report

    SciTech Connect

    Matthews, M.L.; Nagel, J.

    1991-09-01

    The inactive uranium mill tailings site near Lowman, Idaho, was designated as one of 24 abandoned uranium tailings sites to be remediated by the US Department of Energy (DOE) under the Uranium Mill Tailings Radiation Control Act of 1978 (UMTRCA). The UMTRCA requires that the US Nuclear Regulatory Commission (NRC) concur with the DOE`s remedial action plan and certify that the remedial action complies with the standards promulgated by the US Environmental Protection Agency (EPA). The remedial action plan (RAP), which includes this remedial action selection report (RAS), has been developed to serve a two-fold purpose. First, it describes the activities that are proposed by the DOE to accomplish long-term stabilization and control of residual radioactive materials at the inactive uranium processing site near Lowman, Idaho. Second, this document and the remainder of the RAP, upon concurrence and execution by the DOE, the State of Idaho, and the NRC, becomes Appendix B of the Cooperative Agreement (No. DE-FC04-85AL20535) between the DOE and the State of Idaho.

  12. Molecular Basis for Enzymatic Sulfite Oxidation -- HOW THREE CONSERVED ACTIVE SITE RESIDUES SHAPE ENZYME ACTIVITY

    SciTech Connect

    Bailey, Susan; Rapson, Trevor; Johnson-Winters, Kayunta; Astashkin, Andrei; Enemark, John; Kappler, Ulrike

    2008-11-10

    Sulfite dehydrogenases (SDHs) catalyze the oxidation and detoxification of sulfite to sulfate, a reaction critical to all forms of life. Sulfite-oxidizing enzymes contain three conserved active site amino acids (Arg-55, His-57, and Tyr-236) that are crucial for catalytic competency. Here we have studied the kinetic and structural effects of two novel and one previously reported substitution (R55M, H57A, Y236F) in these residues on SDH catalysis. Both Arg-55 and His-57 were found to have key roles in substrate binding. An R55M substitution increased Km(sulfite)(app) by 2-3 orders of magnitude, whereas His-57 was required for maintaining a high substrate affinity at low pH when the imidazole ring is fully protonated. This effect may be mediated by interactions of His-57 with Arg-55 that stabilize the position of the Arg-55 side chain or, alternatively, may reflect changes in the protonation state of sulfite. Unlike what is seen for SDHWT and SDHY236F, the catalytic turnover rates of SDHR55M and SDHH57A are relatively insensitive to pH (~;;60 and 200 s-1, respectively). On the structural level, striking kinetic effects appeared to correlate with disorder (in SDHH57A and SDHY236F) or absence of Arg-55 (SDHR55M), suggesting that Arg-55 and the hydrogen bonding interactions it engages in are crucial for substrate binding and catalysis. The structure of SDHR55M has sulfate bound at the active site, a fact that coincides with a significant increase in the inhibitory effect of sulfate in SDHR55M. Thus, Arg-55 also appears to be involved in enabling discrimination between the substrate and product in SDH.

  13. Identification of inhibitors against the potential ligandable sites in the active cholera toxin.

    PubMed

    Gangopadhyay, Aditi; Datta, Abhijit

    2015-04-01

    The active cholera toxin responsible for the massive loss of water and ions in cholera patients via its ADP ribosylation activity is a heterodimer of the A1 subunit of the bacterial holotoxin and the human cytosolic ARF6 (ADP Ribosylation Factor 6). The active toxin is a potential target for the design of inhibitors against cholera. In this study we identified the potential ligandable sites of the active cholera toxin which can serve as binding sites for drug-like molecules. By employing an energy-based approach to identify ligand binding sites, and comparison with the results of computational solvent mapping, we identified two potential ligandable sites in the active toxin which can be targeted during structure-based drug design against cholera. Based on the probe affinities of the identified ligandable regions, docking-based virtual screening was employed to identify probable inhibitors against these sites. Several indole-based alkaloids and phosphates showed strong interactions to the important residues of the ligandable region at the A1 active site. On the other hand, 26 top scoring hits were identified against the ligandable region at the A1 ARF6 interface which showed strong hydrogen bonding interactions, including guanidines, phosphates, Leucopterin and Aristolochic acid VIa. This study has important implications in the application of hybrid structure-based and ligand-based methods against the identified ligandable sites using the identified inhibitors as reference ligands, for drug design against the active cholera toxin.

  14. Barium ions selectively activate BK channels via the Ca2+-bowl site.

    PubMed

    Zhou, Yu; Zeng, Xu-Hui; Lingle, Christopher J

    2012-07-10

    Activation of Ca(2+)-dependent BK channels is increased via binding of micromolar Ca(2+) to two distinct high-affinity sites per BK α-subunit. One site, termed the Ca(2+) bowl, is embedded within the second RCK domain (RCK2; regulator of conductance for potassium) of each α-subunit, while oxygen-containing residues in the first RCK domain (RCK1) have been linked to a separate Ca(2+) ligation site. Although both sites are activated by Ca(2+) and Sr(2+), Cd(2+) selectively favors activation via the RCK1 site. Divalent cations of larger ionic radius than Sr(2+) are thought to be ineffective at activating BK channels. Here we show that Ba(2+), better known as a blocker of K(+) channels, activates BK channels and that this effect arises exclusively from binding at the Ca(2+)-bowl site. Compared with previous estimates for Ca(2+) bowl-mediated activation by Ca(2+), the affinity of Ba(2+) to the Ca(2+) bowl is reduced about fivefold, and coupling of binding to activation is reduced from ∼3.6 for Ca(2+) to about ∼2.8 for Ba(2+). These results support the idea that ionic radius is an important determinant of selectivity differences among different divalent cations observed for each Ca(2+)-binding site.

  15. Activation of brown adipose tissue mitochondrial GDP binding sites

    SciTech Connect

    Swick, A.G.

    1987-01-01

    The primary function of brown adipose tissue (BAT) is heat production. This ability is attributed to the existence of a unique inner mitochondrial membrane protein termed the uncoupling protein or thermogenin. This protein is permeable to H+ and thus allows respiration (and therefore thermogenesis) to proceed at a rapid rate, independent of ADP phosphorylation. Proton conductance can be inhibited by the binding of purine nucleotides to the uncoupling protein. The binding of (/sup 3/H)-GDP to BAT mitochondria is frequently used as a measure of BAT thermogenic activity. Rats fed a diet that was low but adequate in protein exhibited a decrease in feed efficiency. In addition, BAT thermogenesis was activated as indicated by an elevation in the level of GDP binding to BAT mitochondria. This phenomena occurred in older rats and persisted over time.

  16. Structure and Reactivity of the Phosphotriesterase Active Site

    DTIC Science & Technology

    2002-01-01

    characterize different catalytic conformations for chorismate mutase . Preliminary evidence for water binding in phosphotriesterase suggests that activity in...MD/QM study of the chorismate mutase catalyzed Claisen rearrangement reaction. 2001.subm. J.Phys.Chem.B 22.Day, P.N.J., J.H.; Gordon,M.S.; Webb,S.P...Claisen rearrangement of an unusual substrate in chorismate mutase . 2001.subm. J.Phys.Chem.B 38.Stevens, W.J., Basch,H., Krauss,M., Compact effective

  17. Fort Devens Feasibility Study (FS) for Group 1A Sites, Final Data Gap Activities Work Plan

    DTIC Science & Technology

    1993-03-01

    function and value assessment. Macroinvertebrate studies at both landfills will be conducted to evaluate whether the benthic macroinvertebrate ...Davies (1987) provides instructions for sorting collected benthic macroinvertebrate samples. Macroinvertebrates will be identified to the genus or...4.2 RATIONALE AND PLAN FOR WETLAND FUNCTIONAL ASSESSMENT ...................................... 4-5 4.3 RATIONALE AND PLANS FOR MACROINVERTEBRATE 3

  18. Synthesis of Zn-MOF incorporating titanium-hydrides as active sites binding H2 molecules

    NASA Astrophysics Data System (ADS)

    Kim, Jongsik; Ok Kim, Dong; Wook Kim, Dong; Sagong, Kil

    2015-10-01

    This paper describes the synthetic effort for a Zn-MOF imparting Ti-H as a preferential binding site potentially capturing H2 molecules via Kubas-type interaction. The formation mechanism of Ti-H innate to the final material was potentially demonstrated to follow a radical dissociation rather than a β-hydrogen elimination and a C-H reductive elimination.

  19. Active site proton delivery and the lyase activity of human CYP17A1

    SciTech Connect

    Khatri, Yogan; Gregory, Michael C.; Grinkova, Yelena V.; Denisov, Ilia G.; Sligar, Stephen G.

    2014-01-03

    equivalents and protons are funneled into non-productive pathways. This is similar to previous work with other P450 catalyzed hydroxylation. However, catalysis of carbon–carbon bond scission by the T306A mutant was largely unimpeded by disruption of the CYP17A1 acid-alcohol pair. The unique response of CYP17A1 lyase activity to mutation of Thr306 is consistent with a reactive intermediate formed independently of proton delivery in the active site, and supports involvement of a nucleophilic peroxo-anion rather than the traditional Compound I in catalysis.

  20. Pathways of H2 toward the Active Site of [NiFe]-Hydrogenase

    PubMed Central

    Teixeira, Vitor H.; Baptista, António M.; Soares, Cláudio M.

    2006-01-01

    Hydrogenases catalyze the reversible oxidation of molecular hydrogen (H2), but little is known about the diffusion of H2 toward the active site. Here we analyze pathways for H2 permeation using molecular dynamics (MD) simulations in explicit solvent. Various MD simulation replicates were done, to improve the sampling of the system states. H2 easily permeates hydrogenase in every simulation and it moves preferentially in channels. All H2 molecules that reach the active site made their approach from the side of the Ni ion. H2 is able to reach distances of <4 Å from the active site, although after 6 Å permeation is difficult. In this region we mutated Val-67 into alanine and perform new MD simulations. These simulations show an increase of H2 inside the protein and at lower distances from the active site. This valine can be a control point in the H2 access to the active center. PMID:16731562

  1. Maintenance of plastid RNA editing activities independently of their target sites.

    PubMed

    Tillich, Michael; Poltnigg, Peter; Kushnir, Sergei; Schmitz-Linneweber, Christian

    2006-03-01

    RNA editing in plant organelles is mediated by site-specific, nuclear-encoded factors. Previous data suggested that the maintenance of these factors depends on the presence of their rapidly evolving cognate sites. The surprising ability of allotetraploid Nicotiana tabacum (tobacco) to edit a foreign site in the chloroplast ndhA messenger RNA was thought to be inherited from its diploid male ancestor, Nicotiana tomentosiformis. Here, we show that the same ndhA editing activity is also present in Nicotiana sylvestris, which is the female diploid progenitor of tobacco and which lacks the ndhA site. Hence, heterologous editing is not simply a result of tobacco's allopolyploid genome organization. Analyses of other editing sites after sexual or somatic transfer between land plants showed that heterologous editing occurs at a surprisingly high frequency. This suggests that the corresponding editing activities are conserved despite the absence of their target sites, potentially because they serve other functions in the plant cell.

  2. A Processive Carbohydrate Polymerase That Mediates Bifunctional Catalysis Using a Single Active Site

    PubMed Central

    May, John F.; Levengood, Matthew R.; Splain, Rebecca A.; Brown, Christopher D.; Kiessling, Laura L.

    2012-01-01

    Even in the absence of a template, glycosyltransferases can catalyze the synthesis of carbohydrate polymers of specific sequence. The paradigm has been that one enzyme catalyzes the formation of one type of glycosidic linkage, yet certain glycosyltransferases generate polysaccharide sequences composed of two distinct linkage types. In principle, bifunctional glycosyltransferases can possess separate active sites for each catalytic activity or one active site with dual activities. We encountered the fundamental question of one or two distinct active sites in our investigation of the galactosyltransferase GlfT2. GlfT2 catalyzes the formation of mycobacterial galactan, a critical cell-wall polymer composed of galactofuranose residues connected with alternating, regioisomeric linkages. We found that GlfT2 mediates galactan polymerization using only one active site that manifests dual regioselectivity. Structural modeling of the bifunctional glycosyltransferases hyaluronan synthase and cellulose synthase suggests that these enzymes also generate multiple glycosidic linkages using a single active site. These results highlight the versatility of glycosyltransferases for generating polysaccharides of specific sequence. We postulate that a hallmark of processive elongation of a carbohydrate polymer by a bifunctional enzyme is that one active site can give rise to two separate types of glycosidic bonds. PMID:22217153

  3. Monitoring Soil Erosion on a Burned Site in the Mojave-Great Basin Transition Zone: Final Report for the Jacob Fire Site

    SciTech Connect

    Miller, Julianne; Etyemezian, Vic; Cablk, Mary E.; Shillito, Rose; Shafer, David

    2013-06-01

    A historic return interval of 100 years for large fires in the U.S. southwestern deserts is being replaced by one where fires may reoccur as frequently as every 20 to 30 years. The shortened return interval, which translates to an increase in fires, has implications for management of Soil Corrective Action Units (CAUs) and Corrective Action Sites (CASs) for which the Department of Energy, National Nuclear Security Administration Nevada Field Office has responsibility. A series of studies was initiated at uncontaminated analog sites to better understand the possible impacts of erosion and transport by wind and water should contaminated soil sites burn. The first of these studies was undertaken at the Jacob Fire site approximately 12 kilometers (7.5 miles) north of Hiko, Nevada. A lightning-caused fire burned approximately 200 hectares during August 6-8, 2008. The site is representative of a transition between Mojave and Great Basin desert ecoregions on the Nevada National Security Site (NNSS), where the largest number of Soil CAUs/CASs are located. The area that burned at the Jacob Fire site was primarily a Coleogyne ramosissima (blackbrush) and Ephedra nevadensis (Mormon tea) community, also an abundant shrub assemblage in the similar transition zone on the NNSS. This report summarizes three years of measurements after the fire. Seven measurement campaigns at the Jacob Fire site were completed. Measurements were made on burned ridge (upland) and drainage sites, and on burned and unburned sites beneath and between vegetation. A Portable In-Situ Wind Erosion Lab (PI-SWERL) was used to estimate emissions of suspended particles at different wind speeds. Context for these measurements was provided through a meteorological tower that was installed at the Jacob Fire site to obtain local, relevant environmental parameters. Filter samples, collected from the exhaust of the PI-SWERL during measurements, were analyzed for chemical composition. Runoff and water erosion were

  4. Identification of B. anthracis N(5)-carboxyaminoimidazole ribonucleotide mutase (PurE) active site binding compounds via fragment library screening.

    PubMed

    Lei, Hao; Jones, Christopher; Zhu, Tian; Patel, Kavankumar; Wolf, Nina M; Fung, Leslie W-M; Lee, Hyun; Johnson, Michael E

    2016-02-15

    The de novo purine biosynthesis pathway is an attractive target for antibacterial drug design, and PurE from this pathway has been identified to be crucial for Bacillus anthracis survival in serum. In this study we adopted a fragment-based hit discovery approach, using three screening methods-saturation transfer difference nucleus magnetic resonance (STD-NMR), water-ligand observed via gradient spectroscopy (WaterLOGSY) NMR, and surface plasmon resonance (SPR), against B. anthracis PurE (BaPurE) to identify active site binding fragments by initially testing 352 compounds in a Zenobia fragment library. Competition STD NMR with the BaPurE product effectively eliminated non-active site binding hits from the primary hits, selecting active site binders only. Binding affinities (dissociation constant, KD) of these compounds varied between 234 and 301μM. Based on test results from the Zenobia compounds, we subsequently developed and applied a streamlined fragment screening strategy to screen a much larger library consisting of 3000 computationally pre-selected fragments. Thirteen final fragment hits were confirmed to exhibit binding affinities varying from 14μM to 700μM, which were categorized into five different basic scaffolds. All thirteen fragment hits have ligand efficiencies higher than 0.30. We demonstrated that at least two fragments from two different scaffolds exhibit inhibitory activity against the BaPurE enzyme.

  5. Mechanistic pathways of mercury removal from the organomercurial lyase active site

    PubMed Central

    Rodrigues, Viviana

    2015-01-01

    Bacterial populations present in Hg-rich environments have evolved biological mechanisms to detoxify methylmercury and other organometallic mercury compounds. The most common resistance mechanism relies on the H+-assisted cleavage of the Hg–C bond of methylmercury by the organomercurial lyase MerB. Although the initial reaction steps which lead to the loss of methane from methylmercury have already been studied experimentally and computationally, the reaction steps leading to the removal of Hg2+ from MerB and regeneration of the active site for a new round of catalysis have not yet been elucidated. In this paper, we have studied the final steps of the reaction catalyzed by MerB through quantum chemical computations at the combined MP2/CBS//B3PW91/6-31G(d) level of theory. While conceptually simple, these reaction steps occur in a complex potential energy surface where several distinct pathways are accessible and may operate concurrently. The only pathway which clearly emerges as forbidden in our analysis is the one arising from the sequential addition of two thiolates to the metal atom, due to the accumulation of negative charges in the active site. The addition of two thiols, in contrast, leads to two feasible mechanistic possibilities. The most straightforward pathway proceeds through proton transfer from the attacking thiol to Cys159 , leading to its removal from the mercury coordination sphere, followed by a slower attack of a second thiol, which removes Cys96. The other pathway involves Asp99 in an accessory role similar to the one observed earlier for the initial stages of the reaction and affords a lower activation enthalpy, around 14 kcal mol−1, determined solely by the cysteine removal step rather than by the thiol ligation step. Addition of one thiolate to the intermediates arising from either thiol attack occurs without a barrier and produces an intermediate bound to one active site cysteine and from which Hg(SCH3)2 may be removed only after

  6. Superfund Record of Decision (EPA Region 3): Voortman Farm Site, Lehigh County, Pennsylvania (first remedial action) June 1988. Final report

    SciTech Connect

    Not Available

    1988-06-30

    The 43-acre Voortman Farm site is located in Upper Salucon Township, Lehigh County, Pennsylvania. The site consists of a sinkhole that contained empty battery casings disposed of in late 1979 and early 1980. Citizen complaints in 1980 prompted the prohibition of dumping and subsequent site investigation. In September 1986, the battery casings in the sinkhole caught on fire. Since the battery casings were burning underground, attempts to extinguish the fire remained unsuccessful. There does not appear to be any leaching from any residual metals, contaminated soils or battery casings present. The selected remedial action for the site is included.

  7. Final Environmental Assessment and Finding of No Significant Impact: Ground Water Compliance at the Slick Rock, Colorado, UMTRA Project Site

    SciTech Connect

    N /A

    2003-03-13

    This environmental assessment addresses the environmental effects of a proposed action and the no action alternative to comply with U.S. Environmental Protection Agency (EPA) ground water standards at the Slick Rock, Colorado, Uranium Mill Tailings Remedial Action Project sites. The sites consist of two areas designated as the North Continent (NC) site and the Union Carbide (UC) site. In 1996, the U.S. Department of Energy (DOE) completed surface cleanup at both sites and encapsulated the tailings in a disposal cell 5 miles east of the original sites. Maximum concentration limits (MCLs) referred to in this environmental assessment are the standards established in Title 40 ''Code of Federal Regulations'' Part 192 (40 CFR 192) unless noted otherwise. Ground water contaminants of potential concern at the NC site are uranium and selenium. Uranium is more prevalent, and concentrations in the majority of alluvial wells at the NC site exceed the MCL of 0.044 milligram per liter (mg/L). Selenium contamination is less prevalent; samples from only one well had concentrations exceeding the MCL of 0.01 mg/L. To achieve compliance with Subpart B of 40 CFR 192 at the NC site, DOE is proposing the strategy of natural flushing in conjunction with institutional controls and continued monitoring. Ground water flow and transport modeling has predicted that concentrations of uranium and selenium in the alluvial aquifer will decrease to levels below their respective MCLs within 50 years.

  8. Tetrodotoxin binding sites in human heart and human brain sodium channels. Final report, 28 June 1991-27 June 1994

    SciTech Connect

    Brown, A.M.; Hartmann, H.A.

    1994-07-28

    Tetrodotoxin (TTX) and saxitoxin (STX) are potent and lethal threats to exposed soldiers. The development of an antidote or site-specific antibodies for low affinity TTX/STX cardiac sodium channels and high affinity TTX/STX brain and peripheral nerve sodium channels requires a data base not only of the primary structure of the toxin receptor site(s) but also insight into the secondary structures of these site(s). Five goals or tasks were attempted and the first three were completed. Full-length human cardiac and brain sodium channel cDNAs have been cloned and expressed as functional proteins in Xenopus oocytes. Silent restriction sites have been introduced around the pore or P-region of the Na+ channel repeats. Site-directed mutagenesis has identified critical residues in the pore from the primary structure involved in sensitivity to TTX and STX and other pore properties. Chemical modification of cysteine mutants of these initial residues by methanethiosulfonate compounds produces an expanded data base of the secondary structure of the toxins` receptors. Specific peptides which mimic these receptors will be made to compete with the natural receptor for the toxins. We have successfully cloned the cDNAs for both human heart and brain sodium channels and expressed functional proteins. The initial chemical modification data suggests file receptor sites for TTX/STX are not interchangeable and are not the same site.

  9. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Gunnison, Colorado. Attachment 4, Water resources protection strategy: Final report

    SciTech Connect

    Not Available

    1992-10-01

    To achieve compliance with the proposed US Environmental Protection Agency (EPA) groundwater protection standards the US Department of Energy (DOE) proposes to meet background concentrations or the EPA maximum concentration limits (MCLS) for hazardous constituents in groundwater in the uppermost aquifer at the point of compliance (POC) at the Gunnison Uranium Mill Tailings Remedial Action (UMTRA) Project disposal site near Gunnison, Colorado. The proposed remedial action will ensure protection of human health and the environment. A summary of the principal features of the water resources protection strategy for the Gunnison disposal site is included in this report.

  10. An Accessory Agonist Binding Site Promotes Activation of α4β2* Nicotinic Acetylcholine Receptors*

    PubMed Central

    Wang, Jingyi; Kuryatov, Alexander; Sriram, Aarati; Jin, Zhuang; Kamenecka, Theodore M.; Kenny, Paul J.; Lindstrom, Jon

    2015-01-01

    Neuronal nicotinic acetylcholine receptors containing α4, β2, and sometimes other subunits (α4β2* nAChRs) regulate addictive and other behavioral effects of nicotine. These nAChRs exist in several stoichiometries, typically with two high affinity acetylcholine (ACh) binding sites at the interface of α4 and β2 subunits and a fifth accessory subunit. A third low affinity ACh binding site is formed when this accessory subunit is α4 but not if it is β2. Agonists selective for the accessory ACh site, such as 3-[3-(3-pyridyl)-1,2,4-oxadiazol-5-yl]benzonitrile (NS9283), cannot alone activate a nAChR but can facilitate more efficient activation in combination with agonists at the canonical α4β2 sites. We therefore suggest categorizing agonists according to their site selectivity. NS9283 binds to the accessory ACh binding site; thus it is termed an accessory site-selective agonist. We expressed (α4β2)2 concatamers in Xenopus oocytes with free accessory subunits to obtain defined nAChR stoichiometries and α4/accessory subunit interfaces. We show that α2, α3, α4, and α6 accessory subunits can form binding sites for ACh and NS9283 at interfaces with α4 subunits, but β2 and β4 accessory subunits cannot. To permit selective blockage of the accessory site, α4 threonine 126 located on the minus side of α4 that contributes to the accessory site, but not the α4β2 sites, was mutated to cysteine. Alkylation of this cysteine with a thioreactive reagent blocked activity of ACh and NS9283 at the accessory site. Accessory agonist binding sites are promising drug targets. PMID:25869137

  11. Long-term Bat Monitoring on Islands, Offshore Structures, and Coastal Sites in the Gulf of Maine, mid-Atlantic, and Great Lakes—Final Report

    SciTech Connect

    Peterson, Trevor; Pelletier, Steve; Giovanni, Matt

    2016-01-15

    This report summarizes results of a long-term regional acoustic survey of bat activity at remote islands, offshore structures, and coastal sites in the Gulf of Maine, Great Lakes, and mid-Atlantic coast.

  12. Influence of planetary wave activity on the stratospheric final warming and spring ozone

    NASA Astrophysics Data System (ADS)

    Salby, Murry L.; Callaghan, Patrick F.

    2007-10-01

    A three-dimensional model of dynamics and photochemistry is used to investigate the influence of planetary wave activity on the seasonal evolution of the wintertime stratosphere, which dictates springtime conditions. The final warming and springtime ozone are each found to depend strongly upon planetary wave activity during the disturbed season. The integrations reproduce their observed dependence, which enters through anomalous upward Eliassen-Palm (EP) flux from the troposphere and equatorial wind associated with the Quasi-Biennial Oscillation (QBO). Of those major influences, changes of upward EP flux are predominant. Changes representative of those in the observed record alter the timing of the final warming by as much as 1-2 months. Much the same lag distinguishes warm and cold winters in the observed record. Accompanying the shift in the final warming is a change of ozone at spring equinox. Magnified over the Arctic, anomalous springtime ozone develops largely through anomalous isentropic mixing by planetary waves. Such mixing, which precedes the final warming, incorporates ozone-rich air from lower latitude, leading to enriched polar ozone during spring. Relative to disturbed conditions, springtime polar ozone under undisturbed conditions appears depleted by some 60 DU. Derived through anomalous transport, the same difference characterizes observed changes between warm and cold winters. Much of the apparent depletion is eventually eliminated with the onset of isentropic mixing, as it is in the observed record. Together with anomalous dynamical structure, such behavior has implications important to the interpretation of interannual changes.

  13. Remedial actions at the former Vitro Rare Metals plant site, Canonsburg, Washington County, Pennsylvania. Final Environmental Impact Statement. Volume I

    SciTech Connect

    Not Available

    1983-07-01

    The environmental impacts associated with remedial actions in connection with residual radioactive materials remaining at the inactive uranium processing site located in Canonsburg, Washington County, Pennsylvania are evaluated. The Canonsburg site is an 18.5-acre property that was formerly owned by the Vitro Rare Metals Company. The expanded Canonsburg site would be 30-acre property that would include the Canonsburg site (the former Vitro Rare Metals plant), seven adjacent private houses, and the former Georges Pottery property. During the period 1942 through 1957 the Vitro Manufacturing Company and its successor, the Vitro Corporation of America, processed onsite residues and ores, and government-owned ores, concentrates, and scraps to extract uranium and other rare metals. The Canonsburg site is now the Canon Industrial Park. In addition to storing the residual radioactive materials of this process at the Canonsburg site, about 12,000 tons of radioactively contaminated materials were transferred to a railroad landfill in Burrell Township, Indiana County, Pennsylvania. This Canonsburg FEIS evaluates five alternatives for removing the potential public health hazard associated with the radioactively contaminated materials. In addition to no action, these alternatives involve various combinations of stabilization of the radioactively contaminated materials in place or decontamination of the Canonsburg and Burrell sites by removing the radioactively contaminated materials to another location. In addition to the two sites mentioned, a third site located in Hanover Township, Washington County, Pennsylvania has been considered as a disposal site to which the radioactively contaminated materials presently located at either of the other two sites might be moved.

  14. Activation Analysis of the Final Optics Assemblies at the National Ignition Facility

    SciTech Connect

    Dauffy, L S; Khater, H Y; Sitaraman, S; Brereton, S J

    2008-10-14

    Commissioning shots have commenced at the National Ignition Facility (NIF) at the Lawrence Livermore National Laboratory. Within a year, the 192 laser beam facility will be operational and the experimental phase will begin. At each shot, the emitted neutrons will interact in the facility's surroundings, activating them, especially inside the target bay where the neutron flux is the highest. We are calculating the dose from those activated structures and objects in order to plan and minimize worker exposures during maintenance and normal NIF operation. This study presents the results of the activation analysis of the optics of the Final Optics Assemblies (FOA), which are a key contributor to worker exposure. Indeed, there are 48 FOAs weighting three tons each, and routine change-out and maintenance of optics and optics modules is expected. The neutron field has been characterized using the three-dimensional Monte Carlo particle transport code MCNP with subsequent activation analysis performed using the activation code, ALARA.

  15. Remediation of the site of a former active handling building at UKAEA- Winfrith

    SciTech Connect

    Armitage, Jack; Brown, Nick; Cornell, Rowland; Jessop, Gareth

    2007-07-01

    Available in abstract form only. Full text of publication follows: Since July 2000, NUKEM Limited has been carrying out the decommissioning of the former Active Handling Building, A59 at Winfrith, Dorset, United Kingdom (UK) under contract from the nuclear site licence holder, United Kingdom Atomic Energy Authority, (UKAEA). The building contained two heavily shielded suites of caves originally used to carry out remote examination of irradiated nuclear fuel elements and other supporting facilities which have all been decontaminated ready to permit building demolition. The demolition of the building structure and the removal of one cave line was completed during 2006 and the second cave line was demolished by March 2007. The remaining operations to be completed concern removal of the building slab and remediation of underlying soils to the final end point, free for unrestricted use without planning or nuclear regulatory control. Within the building base slab there are a range of contaminated items including secondary drain pipes, filter pits, storage hole liners and ventilation ducts which all have to be recovered for disposal along with around 4,000 m{sup 3} of surrounding concrete. In order to characterise the slab before its removal, supporting information has been obtained from site investigation work including a collimated low resolution, high sensitivity gamma survey using the GroundhogTM system of the foundation slab and the recovery and analysis of 27 cores obtained by drilling through the slab into the underlying soil. During removal of the slab it will be necessary to employ a variety of monitoring techniques to locate and remove the contaminated sections and then expose and monitor the underlying soil for evidence of any residual radioactivity. (authors)

  16. Experimental and computational active site mapping as a starting point to fragment-based lead discovery.

    PubMed

    Behnen, Jürgen; Köster, Helene; Neudert, Gerd; Craan, Tobias; Heine, Andreas; Klebe, Gerhard

    2012-02-06

    Small highly soluble probe molecules such as aniline, urea, N-methylurea, 2-bromoacetate, 1,2-propanediol, nitrous oxide, benzamidine, and phenol were soaked into crystals of various proteins to map their binding pockets and to detect hot spots of binding with respect to hydrophobic and hydrophilic properties. The selected probe molecules were first tested at the zinc protease thermolysin. They were then applied to a wider range of proteins such as protein kinase A, D-xylose isomerase, 4-diphosphocytidyl-2C-methyl-D-erythritol synthase, endothiapepsin, and secreted aspartic protease 2. The crystal structures obtained clearly show that the probe molecules populate the protein binding pockets in an ordered fashion. The thus characterized, experimentally observed hot spots of binding were subjected to computational active site mapping using HotspotsX. This approach uses knowledge-based pair potentials to detect favorable binding positions for various atom types. Good agreement between the in silico hot spot predictions and the experimentally observed positions of the polar hydrogen bond forming functional groups and hydrophobic portions was obtained. Finally, we compared the observed poses of the small-molecule probes with those of much larger structurally related ligands. They coincide remarkably well with the larger ligands, considering their spatial orientation and the experienced interaction patterns. This observation confirms the fundamental hypothesis of fragment-based lead discovery: that binding poses, even of very small molecular probes, do not significantly deviate or move once a ligand is grown further into the binding site. This underscores the fact that these probes populate given hot spots and can be regarded as relevant seeds for further design.

  17. ENVIRONMENTAL ASSESSMENT OF OKLAHOMA ABANDONED DRILLING AND PRODUCTION SITES AND ASSOCIATED PUBLIC EDUCATION/OUTREACH ACTIVITIES

    SciTech Connect

    Mike Terry

    2002-03-01

    The U.S. Department of Energy has participated with the Oklahoma Energy Resource Board (OERB) since 1995 by providing grant funding for on-going work in both environmental assessment of abandoned oilfield exploration and production sites and associated public education/outreach activities. The OERB, a state agency created in 1993 by the Oklahoma legislature, administers programs funded by an assessment of one tenth of one percent on all oil and natural gas produced and sold in the state of Oklahoma. Approximately one half of the funds are used to assess and remediate abandoned oilfield sites and the other half are being used to educate about the importance of the oil and natural gas industry and OERB's environmental efforts. Financial participation through grant funding by the U.S. D.O.E. has been $200,000 annually which represents approximately 3 percent of OERB's private funding. Most of OERB's revenues come from an assessment of 1/10th of 1% on the sale of crude and natural gas in Oklahoma. The assessment is considered voluntary in that any interest owner may ask for a refund annually of their contributions to the fund. On average, 95% of the assessment dollars have remained with OERB, which shows tremendous support by the industry. This Final Report summarizes the progress of the three year grant. The purpose of this three-year project was to continue the progress of the OERB to accomplish its environmental and educational objectives and transfer information learned to other organizations and producing states in the industry.

  18. Extending the Diffuse Layer Model of Surface Acidity Behavior: III. Estimating Bound Site Activity Coefficients

    EPA Science Inventory

    Although detailed thermodynamic analyses of the 2-pK diffuse layer surface complexation model generally specify bound site activity coefficients for the purpose of accounting for those non-ideal excess free energies contributing to bound site electrochemical potentials, in applic...

  19. 75 FR 71677 - Reimbursement for Costs of Remedial Action at Active Uranium and Thorium Processing Sites

    Federal Register 2010, 2011, 2012, 2013, 2014

    2010-11-24

    ... Reimbursement for Costs of Remedial Action at Active Uranium and Thorium Processing Sites AGENCY: Department of... uranium and thorium processing site licensees for reimbursement under Title X of the Energy Policy Act of... requires DOE to reimburse eligible uranium and thorium licensees for certain costs of...

  20. Initial field trials of the site characterization and analysis penetrometer system (SCAPS). Reconnaissance of Jacksonville Naval Air Station waste oil and solvents disposal site. Final report

    SciTech Connect

    Cooper, S.S.; Douglas, D.H.; Sharp, M.K.; Olsen, R.A.; Comes, G.D.

    1993-12-01

    At the request of the Naval Facilities Engineering Command (NAVFAC), Southern Division, Charleston, SC, the U.S. Army Engineer Waterways Experiment Station (WES) conducted the initial field trial of the Site Characterization and Analysis Penetrometer System (SCAPS) at Jacksonville Naval Air Station (NAS), Jacksonville FL. This work was carried out by a field crew consisting of personnel from WES and the Naval Ocean Systems Center during the period of 16 July 1990 to 14 August 1990. The SCAPS investigation at the Jacksonville NAS has two primary objectives: (a) to provide data that could be useful in formulating remediation plans for the facility and (b) to provide for the initial field trial of the SCAPS currently under development by WES for the U.S. Army Toxic and Hazardous Materials Agency (USATHAMA), now the U.S. Army Environmental Center. The original concepts for the SCAPS was to develop an integrated site screening characterization system whose capabilities would include (a) surface mapping, (b) geophysical surveys using magnetic, induced electromagnetic, and radar instruments, (c) measurements of soil strength, soil electrical resistivity, and laser-induced soil fluorometry Cone penetrometer, Site Characterization and Analysis Laser Induced Fluorescence(LIF), Penetrometer System(SCAPS) POL Contamination, using screening instrumentation mounted in a soil penetrometer, (d) soil and fluid samplers, and (e) computerized data acquisition, interpretation, and visualization. The goal of the SCAPS program is to provide detailed, rapid, and cost-effective surface and subsurface data for input to site assessment/remediation efforts.

  1. 40 CFR 61.154 - Standard for active waste disposal sites.

    Code of Federal Regulations, 2013 CFR

    2013-07-01

    ...). (e) For all asbestos-containing waste material received, the owner or operator of the active waste... 40 Protection of Environment 9 2013-07-01 2013-07-01 false Standard for active waste disposal... for Asbestos § 61.154 Standard for active waste disposal sites. Each owner or operator of an...

  2. Proposed ground water protection strategy for the Uranium Mill Tailings Site at Green River, Utah. Final report

    SciTech Connect

    Not Available

    1994-11-01

    This document presents the US DOE water resources protection strategy for the Green River, Utah mill tailings disposal site. The modifications in the original plan are based on new information, including ground water quality data collected after remedial action was completed, and on a revised assessment of disposal cell design features, surface conditions, and site hydrogeology. All aspects are discussed in this report.

  3. A vegetation management plan for Fort Union Trading Post National Historic Site: Final report for interagency agreement number F154910005

    USGS Publications Warehouse

    Symstad, Amy J.

    2012-01-01

    Summary: This report provides Fort Union Trading Post National Historic Site, a small NPS unit on the border of Montana and North Dakota, a framework and reasonable tools for future vegetation management at the site in the context of probable historic, current, and desired future vegetation.

  4. Unmasking tandem site interaction in human acetylcholinesterase. Substrate activation with a cationic acetanilide substrate.

    PubMed

    Johnson, Joseph L; Cusack, Bernadette; Davies, Matthew P; Fauq, Abdul; Rosenberry, Terrone L

    2003-05-13

    Acetylcholinesterase (AChE) contains a narrow and deep active site gorge with two sites of ligand binding, an acylation site (or A-site) at the base of the gorge, and a peripheral site (or P-site) near the gorge entrance. The P-site contributes to catalytic efficiency by transiently binding substrates on their way to the acylation site, where a short-lived acyl enzyme intermediate is produced. A conformational interaction between the A- and P-sites has recently been found to modulate ligand affinities. We now demonstrate that this interaction is of functional importance by showing that the acetylation rate constant of a substrate bound to the A-site is increased by a factor a when a second molecule of substrate binds to the P-site. This demonstration became feasible through the introduction of a new acetanilide substrate analogue of acetylcholine, 3-(acetamido)-N,N,N-trimethylanilinium (ATMA), for which a = 4. This substrate has a low acetylation rate constant and equilibrates with the catalytic site, allowing a tractable algebraic solution to the rate equation for substrate hydrolysis. ATMA affinities for the A- and P-sites deduced from the kinetic analysis were confirmed by fluorescence titration with thioflavin T as a reporter ligand. Values of a >1 give rise to a hydrolysis profile called substrate activation, and the AChE site-specific mutant W86F, and to a lesser extent wild-type human AChE itself, showed substrate activation with acetylthiocholine as the substrate. Substrate activation was incorporated into a previous catalytic scheme for AChE in which a bound P-site ligand can also block product dissociation from the A-site, and two additional features of the AChE catalytic pathway were revealed. First, the ability of a bound P-site ligand to increase the substrate acetylation rate constant varied with the structure of the ligand: thioflavin T accelerated ATMA acetylation by a factor a(2) of 1.3, while propidium failed to accelerate. Second, catalytic rate

  5. Structure and nuclearity of active sites in Fe-zeolites: comparison with iron sites in enzymes and homogeneous catalysts.

    PubMed

    Zecchina, Adriano; Rivallan, Mickaël; Berlier, Gloria; Lamberti, Carlo; Ricchiardi, Gabriele

    2007-07-21

    Fe-ZSM-5 and Fe-silicalite zeolites efficiently catalyse several oxidation reactions which find close analogues in the oxidation reactions catalyzed by homogeneous and enzymatic compounds. The iron centres are highly dispersed in the crystalline matrix and on highly diluted samples, mononuclear and dinuclear structures are expected to become predominant. The crystalline and robust character of the MFI framework has allowed to hypothesize that the catalytic sites are located in well defined crystallographic positions. For this reason these catalysts have been considered as the closest and best defined heterogeneous counterparts of heme and non heme iron complexes and of Fenton type Fe(2+) homogeneous counterparts. On this basis, an analogy with the methane monooxygenase has been advanced several times. In this review we have examined the abundant literature on the subject and summarized the most widely accepted views on the structure, nuclearity and catalytic activity of the iron species. By comparing the results obtained with the various characterization techniques, we conclude that Fe-ZSM-5 and Fe-silicalite are not the ideal samples conceived before and that many types of species are present, some active and some other silent from adsorptive and catalytic point of view. The relative concentration of these species changes with thermal treatments, preparation procedures and loading. Only at lowest loadings the catalytically active species become the dominant fraction of the iron species. On the basis of the spectroscopic titration of the active sites by using NO as a probe, we conclude that the active species on very diluted samples are isolated and highly coordinatively unsaturated Fe(2+) grafted to the crystalline matrix. Indication of the constant presence of a smaller fraction of Fe(2+) presumably located on small clusters is also obtained. The nitrosyl species formed upon dosing NO from the gas phase on activated Fe-ZSM-5 and Fe-silicalite, have been analyzed

  6. Health assessment for Waste Disposal Engineering, Inc. Sanitary Landfill site, Andover, Minnesota, Region 5. CERCLIS No. MND980609119. Final report

    SciTech Connect

    Not Available

    1988-04-01

    Waste Disposal Engineering Inc. Sanitary Landfill, is an NPL site located in the City of Andover. The 173-acre site was used to landfill municipal refuse and industrial wastes. Volatile organic compounds and lime sludge are the predominant contaminants present at the landfill. Exposure pathways for the site are the following: ingestion of surface water, ground water, sediment, and lime sludge; inhalation of dusts and vapors generated on-site; and dermal exposure to surface water, sediment, lime sludge, ground water, and exposed waste. The remedial action proposed will address major health concerns for the site. There is public health concern regarding inhalation and dermal absorption of lime sludge (particularly to the fugitive dust generated) and vapors, as well as ingestion exposure to the lime sludge.

  7. Monocopper active site for partial methane oxidation in Cu-exchanged 8MR zeolites

    SciTech Connect

    Kulkarni, Ambarish R.; Zhao, Zhi -Jian; Siahrostami, Samira; Nørskov, Jens K.; Studt, Felix

    2016-08-17

    Direct conversion of methane to methanol using oxygen is experiencing renewed interest owing to the availability of new natural gas resources. Copper-exchanged zeolites such as mordenite and ZSM-5 have shown encouraging results, and di- and tri-copper species have been suggested as active sites. Recently, small eight-membered ring (8MR) zeolites including SSZ-13, -16, and -39 have been shown to be active for methane oxidation, but the active sites and reaction mechanisms in these 8MR zeolites are not known. In this work, we use density functional theory (DFT) calculations to systematically evaluate monocopper species as active sites for the partial methane oxidation reaction in Cu-exchanged SSZ-13. On the basis of kinetic and thermodynamic arguments, we suggest that [CuIIOH]+ species in the 8MR are responsible for the experimentally observed activity. Furthermore, our results successfully explain the available spectroscopic data and experimental observations including (i) the necessity of water for methanol extraction and (ii) the effect of Si/Al ratio on the catalyst activity. Monocopper species have not yet been suggested as an active site for the partial methane oxidation reaction, and our results suggest that [CuIIOH]+ active site may provide complementary routes for methane activation in zeolites in addition to the known [Cu–O–Cu]2+ and Cu3O3 motifs.

  8. Monocopper active site for partial methane oxidation in Cu-exchanged 8MR zeolites

    DOE PAGES

    Kulkarni, Ambarish R.; Zhao, Zhi -Jian; Siahrostami, Samira; ...

    2016-08-17

    Direct conversion of methane to methanol using oxygen is experiencing renewed interest owing to the availability of new natural gas resources. Copper-exchanged zeolites such as mordenite and ZSM-5 have shown encouraging results, and di- and tri-copper species have been suggested as active sites. Recently, small eight-membered ring (8MR) zeolites including SSZ-13, -16, and -39 have been shown to be active for methane oxidation, but the active sites and reaction mechanisms in these 8MR zeolites are not known. In this work, we use density functional theory (DFT) calculations to systematically evaluate monocopper species as active sites for the partial methane oxidationmore » reaction in Cu-exchanged SSZ-13. On the basis of kinetic and thermodynamic arguments, we suggest that [CuIIOH]+ species in the 8MR are responsible for the experimentally observed activity. Furthermore, our results successfully explain the available spectroscopic data and experimental observations including (i) the necessity of water for methanol extraction and (ii) the effect of Si/Al ratio on the catalyst activity. Monocopper species have not yet been suggested as an active site for the partial methane oxidation reaction, and our results suggest that [CuIIOH]+ active site may provide complementary routes for methane activation in zeolites in addition to the known [Cu–O–Cu]2+ and Cu3O3 motifs.« less

  9. Identifying transcription start sites and active enhancer elements using BruUV-seq.

    PubMed

    Magnuson, Brian; Veloso, Artur; Kirkconnell, Killeen S; de Andrade Lima, Leonardo Carmo; Paulsen, Michelle T; Ljungman, Emily A; Bedi, Karan; Prasad, Jayendra; Wilson, Thomas E; Ljungman, Mats

    2015-12-11

    BruUV-seq utilizes UV light to introduce transcription-blocking DNA lesions randomly in the genome prior to bromouridine-labeling and deep sequencing of nascent RNA. By inhibiting transcription elongation, but not initiation, pre-treatment with UV light leads to a redistribution of transcription reads resulting in the enhancement of nascent RNA signal towards the 5'-end of genes promoting the identification of transcription start sites (TSSs). Furthermore, transcripts associated with arrested RNA polymerases are protected from 3'-5' degradation and thus, unstable transcripts such as putative enhancer RNA (eRNA) are dramatically increased. Validation of BruUV-seq against GRO-cap that identifies capped run-on transcripts showed that most BruUV-seq peaks overlapped with GRO-cap signal over both TSSs and enhancer elements. Finally, BruUV-seq identified putative enhancer elements induced by tumor necrosis factor (TNF) treatment concomitant with expression of nearby TNF-induced genes. Taken together, BruUV-seq is a powerful new approach for identifying TSSs and active enhancer elements genome-wide in intact cells.

  10. Identifying transcription start sites and active enhancer elements using BruUV-seq

    PubMed Central

    Magnuson, Brian; Veloso, Artur; Kirkconnell, Killeen S.; Lima, Leonardo Carmo de Andrade; Paulsen, Michelle T.; Ljungman, Emily A.; Bedi, Karan; Prasad, Jayendra; Wilson, Thomas E.; Ljungman, Mats

    2015-01-01

    BruUV-seq utilizes UV light to introduce transcription-blocking DNA lesions randomly in the genome prior to bromouridine-labeling and deep sequencing of nascent RNA. By inhibiting transcription elongation, but not initiation, pre-treatment with UV light leads to a redistribution of transcription reads resulting in the enhancement of nascent RNA signal towards the 5′-end of genes promoting the identification of transcription start sites (TSSs). Furthermore, transcripts associated with arrested RNA polymerases are protected from 3′–5′ degradation and thus, unstable transcripts such as putative enhancer RNA (eRNA) are dramatically increased. Validation of BruUV-seq against GRO-cap that identifies capped run-on transcripts showed that most BruUV-seq peaks overlapped with GRO-cap signal over both TSSs and enhancer elements. Finally, BruUV-seq identified putative enhancer elements induced by tumor necrosis factor (TNF) treatment concomitant with expression of nearby TNF-induced genes. Taken together, BruUV-seq is a powerful new approach for identifying TSSs and active enhancer elements genome-wide in intact cells. PMID:26656874

  11. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Durango, Colorado: Attachment 6, Supplemental standard for Durango processing site. Revised final report

    SciTech Connect

    Not Available

    1991-12-01

    Excavation control to the 15 pCi/g radium-226 (Ra-226) standard at certain areas along the Animas River on the Durango Site would require extensive engineering and construction support. Elevated Ra-226 concentrations have been encountered immediately adjacent to the river at depths in excess of 7 feet below the present river stage. Decontamination to such depths to ensure compliance with the EPA standards will, in our opinion, become unreasonable. This work does not appear to be in keeping with the intent of the standards. Because the principal reason for radium removal is reduction of radon daughter concentrations (RDC) in homes to be built onsite, and because radon produced at depth will be attenuated in clean fill cover before entering such homes, it is appropriate to calculate the depth of excavation needed under a home to reduce RDC to acceptable levels. Potential impact was assessed through radon emanation estimation, using the RAECOM computer model. Elevated Ra-226 concentrations were encountered during final radium excavation of the flood plain below the large tailings pile, adjacent to the slag area. Data from 7 test pits excavated across the area were analyzed to provide an estimate of the Ra-226 concentration profile. Results are given in this report.

  12. 1993 annual report of hazardous waste activities for the Oak Ridge K-25 site

    SciTech Connect

    Not Available

    1994-02-01

    This report is a detailed listing of all of the Hazardous Waste activities occurring at Martin Marietta`s K-25 site. Contained herein are hazardous waste notification forms, waste stream reports, generator fee forms and various TSDR reports.

  13. The surface chemistry of heterogeneous catalysis: mechanisms, selectivity, and active sites.

    PubMed

    Zaera, Francisco

    2005-01-01

    The role of chemical kinetics in defining the requirements for the active sites of heterogeneous catalysts is discussed. A personal view is presented, with specific examples from our laboratory to illustrate the role of the chemical composition, structure, and electronic properties of specific surface sites in determining reaction activity and selectivity. Manipulation of catalytic behavior via the addition of chemical modifiers and by tuning of the reaction conditions is also introduced.

  14. Final report: survey and removal of radioactive surface contamination at environmental restoration sites, Sandia National Laboratories/New Mexico. Volume 1

    SciTech Connect

    Lambert, K.A.; Mitchell, M.M.; Jean, D.; Byrd, C.S.

    1997-09-01

    This report describes the survey and removal of radioactive surface contamination at Sandia`s Environmental Restoration (ER) sites. Radiological characterization was performed as a prerequisite to beginning the Resource Conservation and Recovery Act (RCRA) corrective action process. The removal of radioactive surface contamination was performed in order to reduce potential impacts to human health and the environment. The predominant radiological contaminant of concern was depleted uranium (DU). Between October 1993 and November 1996 scanning surface radiation surveys, using gamma scintillometers, were conducted at 65 sites covering approximately 908 acres. A total of 9,518 radiation anomalies were detected at 38 sites. Cleanup activities were conducted between October 1994 and November 1996. A total of 9,122 anomalies were removed and 2,072 waste drums were generated. The majority of anomalies not removed were associated with a site that has subsurface contamination beyond the scope of this project. Verification soil samples (1,008 total samples) were collected from anomalies during cleanup activities and confirm that the soil concentration achieved in the field were far below the target cleanup level of 230 pCi/g of U-238 (the primary constituent of DU) in the soil. Cleanup was completed at 21 sites and no further radiological action is required. Seventeen sites were not completed since cleanup activities wee precluded by ongoing site activity or were beyond the original project scope.

  15. Final closure assessment work plan for sites 2 and 10, 119th Fighter-Interceptor Group, North Dakota Air National Guard Base, Hector Field, Fargo, North Dakota

    SciTech Connect

    1994-06-01

    This Work Plan (WP) outlines closure assessment activities to be conducted at two sites at the North Dakota Air National Guard (NDANG) Base, Hector International Airport (also known as Hector Field), Fargo, North Dakota. The sites to be assessed include one 300-gal nominal capacity waste oil underground storage tank (UST) which is scheduled to be removed (Site 2), and a former fire training area (Site 10) where removal of contaminated soils is scheduled. The objectives of the assessment are to provide documentation of soil and water conditions following excavation of the UST at Site 2 and excavation of contaminated soils at Site 10 in order to support closure in accordance with applicable North Dakota State Department of Health and Consolidated Laboratories requirements.

  16. Two active site divalent ions in the crystal structure of the hammerhead ribozyme bound to a transition state analogue

    DOE PAGES

    Mir, Aamir; Golden, Barbara L.

    2015-11-09

    The crystal structure of the hammerhead ribozyme bound to the pentavalent transition state analogue vanadate reveals significant rearrangements relative to the previously determined structures. The active site contracts, bringing G10.1 closer to the cleavage site and repositioning a divalent metal ion such that it could, ultimately, interact directly with the scissile phosphate. This ion could also position a water molecule to serve as a general acid in the cleavage reaction. A second divalent ion is observed coordinated to O6 of G12. This metal ion is well-placed to help tune the pKA of G12. Finally, on the basis of this crystalmore » structure as well as a wealth of biochemical studies, in this paper we propose a mechanism in which G12 serves as the general base and a magnesium-bound water serves as a general acid.« less

  17. Two active site divalent ions in the crystal structure of the hammerhead ribozyme bound to a transition state analogue

    SciTech Connect

    Mir, Aamir; Golden, Barbara L.

    2015-11-09

    The crystal structure of the hammerhead ribozyme bound to the pentavalent transition state analogue vanadate reveals significant rearrangements relative to the previously determined structures. The active site contracts, bringing G10.1 closer to the cleavage site and repositioning a divalent metal ion such that it could, ultimately, interact directly with the scissile phosphate. This ion could also position a water molecule to serve as a general acid in the cleavage reaction. A second divalent ion is observed coordinated to O6 of G12. This metal ion is well-placed to help tune the pKA of G12. Finally, on the basis of this crystal structure as well as a wealth of biochemical studies, in this paper we propose a mechanism in which G12 serves as the general base and a magnesium-bound water serves as a general acid.

  18. Nuclear waste: Status of DOE`s nuclear waste site characterization activities

    SciTech Connect

    1987-12-31

    Three potential nuclear waste repository sites have been selected to carry out characterization activities-the detailed geological testing to determine the suitability of each site as a repository. The sites are Hanford in south-central Washington State, Yucca Mountain in southern Nevada, and Deaf Smith in the Texas Panhandle. Two key issues affecting the total program are the estimations of the site characterization completion data and costs and DOE`s relationship with the Nuclear Regulatory Commission which has been limited and its relations with affected states and Indian tribes which continue to be difficult.

  19. Remedial action plan and site design for stabilization of the inactive uranium mill tailings sites at Slick Rock, Colorado: Remedial Action Selection Report. Preliminary final

    SciTech Connect

    Not Available

    1994-03-01

    This proposed remedial action plan incorporates the results of detailed investigation of geologic, geomorphic, and seismic conditions at the proposed disposal site. The proposed remedial action will consist of relocating the uranium mill tailings, contaminated vicinity property materials, demolition debris, and windblown/waterborne materials to a permanent repository at the proposed Burro Canyon disposal cell. The proposed disposal site will be geomorphically stable. Seismic design parameters were developed for the geotechnical analyses of the proposed cell. Cell stability was analyzed to ensure long-term performance of the disposal cell in meeting design standards, including slope stability, settlement, and liquefaction potential. The proposed cell cover and erosion protection features were also analyzed and designed to protect the RRM (residual radioactive materials) against surface water and wind erosion. The location of the proposed cell precludes the need for permanent drainage or interceptor ditches. Rock to be used on the cell top-, side-, and toeslopes was sized to withstand probable maximum precipitation events.

  20. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Rifle, Colorado. Volume 1, Text: Appendices A, B, and C: Final report

    SciTech Connect

    1990-02-01

    This document has been structured to provide a comprehensive understanding of the remedial action proposed for the Rifle sites. That remedial action consists of removing approximately 4,185,000 cubic yards (cy) of tailings and contaminated materials from their current locations, transporting, and stabilizing the tailings material at the Estes Gulch disposal site, approximately six miles north of Rifle. The tailings and contaminated materials are comprised of approximately 597,000 cy from Old Rifle, 3,232,000 cy from New Rifle, and 322,000 cy from vicinity properties and about 34,000 cy from demolition. The remedial action plan includes specific design requirements for the detailed design and construction of the remedial action. An extensive amount of data and supporting information have been generated for this remedial action and cannot all be incorporated into this document. Pertinent information and data are included with reference given to the supporting documents.

  1. Remedial action plan and site design for stabilization of the inactive Uranium Mill Tailings Site at Lowman, Idaho. Attachment 4, Water resources protection strategy: Final report

    SciTech Connect

    Not Available

    1991-09-01

    The DOE proposes to achieve compliance with the proposed EPA groundwater protection standards (Subparts A and B of 40 CFR 192) by meeting the EPA maximum concentration limits (MCLs) or background concentrations for designated hazardous constituents in groundwater in the uppermost aquifer (alluvium/weathered granodiorite) at the point of compliance (POC) at the Lowman disposal site near Lowman, Idaho. The proposed remedial action in conjunction with existing hydrogeological conditions at the Lowman site will ensure sufficient protection of human health and the environment. The DOE has concluded that the EPA groundwater protection standards will be met at the POC because, with the exception of antimony, none of the hazardous constituents that exceed laboratory method detection limits within the radioactive sand pore fluids were above the proposed concentration limits. The DOE has demonstrated that antimony will meet the proposed concentration limits at the POC through attenuation in subsoils beneath the disposal cell and by dilution in groundwater underflow. The Lowman processing site is in compliance with Subpart B of 40 CFR 192 because statistical analyses of groundwater samples indicate no groundwater contamination.

  2. A Hydrophobic Pocket in the Active Site of Glycolytic Aldolase Mediates Interactions with Wiskott-Aldrich Syndrome Protein

    SciTech Connect

    St-Jean,M.; Izard, T.; Sygusch, J.

    2007-01-01

    Aldolase plays essential catalytic roles in glycolysis and gluconeogenesis. However, aldolase is a highly abundant protein that is remarkably promiscuous in its interactions with other cellular proteins. In particular, aldolase binds to highly acidic amino acid sequences, including the C-terminus of the Wiskott-Aldrich syndrome protein, an actin nucleation promoting factor. Here we report the crystal structure of tetrameric rabbit muscle aldolase in complex with a C-terminal peptide of Wiskott-Aldrich syndrome protein. Aldolase recognizes a short, 4-residue DEWD motif (residues 498-501), which adopts a loose hairpin turn that folds about the central aromatic residue, enabling its tryptophan side chain to fit into a hydrophobic pocket in the active site of aldolase. The flanking acidic residues in this binding motif provide further interactions with conserved aldolase active site residues, Arg-42 and Arg-303, aligning their side chains and forming the sides of the hydrophobic pocket. The binding of Wiskott-Aldrich syndrome protein to aldolase precludes intramolecular interactions of its C-terminus with its active site, and is competitive with substrate as well as with binding by actin and cortactin. Finally, based on this structure a novel naphthol phosphate-based inhibitor of aldolase was identified and its structure in complex with aldolase demonstrated mimicry of the Wiskott-Aldrich syndrome protein-aldolase interaction. The data support a model whereby aldolase exists in distinct forms that regulate glycolysis or actin dynamics.

  3. Number and locations of agonist binding sites required to activate homomeric Cys-loop receptors.

    PubMed

    Rayes, Diego; De Rosa, María José; Sine, Steven M; Bouzat, Cecilia

    2009-05-06

    Homo-pentameric Cys-loop receptors contain five identical agonist binding sites, each formed at a subunit interface. To determine the number and locations of binding sites required to generate a stable active state, we constructed a receptor subunit with a mutation that disables the agonist binding site and a reporter mutation that alters unitary conductance and coexpressed mutant and nonmutant subunits. Although receptors with a range of different subunit compositions are produced, patch-clamp recordings reveal that the amplitude of each single-channel opening event reports the number and, for certain subunit combinations, the locations of subunits with intact binding sites. We find that receptors with three binding sites at nonconsecutive subunit interfaces exhibit maximal mean channel open time, receptors with binding sites at three consecutive or two nonconsecutive interfaces exhibit intermediate open time, and receptors with binding sites at two consecutive or one interface exhibit brief open time. Macroscopic recordings after rapid application of agonist reveal that channel activation slows and the extent of desensitization decreases as the number of binding sites per receptor decreases. The overall results provide a framework for defining mechanisms of activation and drug modulation for homo-pentameric Cys-loop receptors.

  4. Health assessment for Beacon Heights Landfill site, Beacon Falls, Connecticut, Region 1. CERCLIS No. CTD072122062. Addendum. Final report

    SciTech Connect

    Not Available

    1991-06-20

    The Beacon Heights Landfill National Priorities List (NPL) Site is located in Beacon Falls, Connecticut. From the 1920's to 1979, municipal and industrial wastes were disposed of at the landfill. Leachate from the landfill has migrated into the local groundwater aquifers. Two residential wells to the northwest of the site have been contaminated with site-related contaminants. This site is of potential public health concern because of the risk to human health resulting from possible exposure to hazardous substances at concentrations that may result in adverse health effects. As noted in Human Exposure Pathways Section below, human exposure to benzene, chlorobenzene, chloroethane, and methylene chloride may have occurred via ingestion, inhalation, and direct dermal contact with contaminated groundwater. No health study follow-up is indicated at this time.

  5. EPA Finalizes $9 Million Interim Cleanup Plan for Expanded Area at CTS of Asheville Inc. Superfund Site

    EPA Pesticide Factsheets

    ATLANTA - The U.S. Environmental Protection Agency has selected an interim cleanup plan to address contamination beneath the former plant at the CTS of Asheville Inc. Superfund Site. The North Carolina Department of Environmental Quality concurred w

  6. Remedial actions at the former Vitro Rare Metals plant site, Canonsburg, Washington County, Pennsylvania. Final Environmental Impact Statement. Volume II. Appendices

    SciTech Connect

    Not Available

    1983-07-01

    This report provides a summary of the conceptual design and other information necessary to understand the proposed remedial action at the expanded Canonsburg, Pennsylvania site. This design constitutes the current approach to stabilizing the radioactively contaminated materials in place in a manner that would fully protect the public health and environment. This summary is intended to provide sufficient detail for the reader to understand the proposed remedial action and the anticipated environmental impacts. The site conceptual design has been developed using available data. In some cases, elements of the design have not been developed fully and will be made final during the detailed design process.

  7. Policy for municipality and municipal solid waste CERCLA settlements at NPL co-disposal sites. Final report

    SciTech Connect

    Herman, S.A.

    1998-02-01

    The purpose of this policy is to provide a fair, consistent, and efficient settlement methodology for resolving the potential liability under CERCLA of generators and transporters of municipal sewage sludge and/or municipal solid waste at co-disposal landfills on the National Priorities List (NPL), and municipal owners and operators of such sites. This policy is intended to reduce transaction costs, including those associated with third-party litigation, and to encourage global settlements at sites.

  8. Molecular dynamics explorations of active site structure in designed and evolved enzymes.

    PubMed

    Osuna, Sílvia; Jiménez-Osés, Gonzalo; Noey, Elizabeth L; Houk, K N

    2015-04-21

    This Account describes the use of molecular dynamics (MD) simulations to reveal how mutations alter the structure and organization of enzyme active sites. As proposed by Pauling about 70 years ago and elaborated by many others since then, biocatalysis is efficient when functional groups in the active site of an enzyme are in optimal positions for transition state stabilization. Changes in mechanism and covalent interactions are often critical parts of enzyme catalysis. We describe our explorations of the dynamical preorganization of active sites using MD, studying the fluctuations between active and inactive conformations normally concealed to static crystallography. MD shows how the various arrangements of active site residues influence the free energy of the transition state and relates the populations of the catalytic conformational ensemble to the enzyme activity. This Account is organized around three case studies from our laboratory. We first describe the importance of dynamics in evaluating a series of computationally designed and experimentally evolved enzymes for the Kemp elimination, a popular subject in the enzyme design field. We find that the dynamics of the active site is influenced not only by the original sequence design and subsequent mutations but also by the nature of the ligand present in the active site. In the second example, we show how microsecond MD has been used to uncover the role of remote mutations in the active site dynamics and catalysis of a transesterase, LovD. This enzyme was evolved by Tang at UCLA and Codexis, Inc., and is a useful commercial catalyst for the production of the drug simvastatin. X-ray analysis of inactive and active mutants did not reveal differences in the active sites, but relatively long time scale MD in solution showed that the active site of the wild-type enzyme preorganizes only upon binding of the acyl carrier protein (ACP) that delivers the natural acyl group to the active site. In the absence of bound ACP

  9. Correlated structural kinetics and retarded solvent dynamics at the metalloprotease active site

    SciTech Connect

    Grossman, Moran; Born, Benjamin; Heyden, Matthias; Tworowski, Dmitry; Fields, Gregg B.; Sagi, Irit; Havenith, Martina

    2011-09-18

    Solvent dynamics can play a major role in enzyme activity, but obtaining an accurate, quantitative picture of solvent activity during catalysis is quite challenging. Here, we combine terahertz spectroscopy and X-ray absorption analyses to measure changes in the coupled water-protein motions during peptide hydrolysis by a zinc-dependent human metalloprotease. These changes were tightly correlated with rearrangements at the active site during the formation of productive enzyme-substrate intermediates and were different from those in an enzyme–inhibitor complex. Molecular dynamics simulations showed a steep gradient of fast-to-slow coupled protein-water motions around the protein, active site and substrate. Our results show that water retardation occurs before formation of the functional Michaelis complex. We propose that the observed gradient of coupled protein-water motions may assist enzyme-substrate interactions through water-polarizing mechanisms that are remotely mediated by the catalytic metal ion and the enzyme active site.

  10. Two interacting binding sites for quinacrine derivatives in the active site of trypanothione reductase – a template for drug design

    PubMed Central

    Saravanamuthu, Ahilan; Vickers, Tim J.; Bond, Charles S.; Peterson, Mark R.; Hunter, William N.; Fairlamb, Alan H.

    2012-01-01

    SUMMARY Trypanothione reductase is a key enzyme in the trypanothione-based redox metabolism of pathogenic trypanosomes. Since this system is absent in humans, being replaced with glutathione and glutathione reductase, it offers a target for selective inhibition. The rational design of potent inhibitors requires accurate structures of enzyme-inhibitor complexes, but this is lacking for trypanothione reductase. We therefore used quinacrine mustard, an alkylating derivative of the competitive inhibitor quinacrine, to probe the active site of this dimeric flavoprotein. Quinacrine mustard irreversibly inactivates Trypanosoma cruzi trypanothione reductase, but not human glutathione reductase, in a time-dependent manner with a stoichiometry of two inhibitors bound per monomer. The rate of inactivation is dependent upon the oxidation state of trypanothione reductase, with the NADPH-reduced form being inactivated significantly faster than the oxidised form. Inactivation is slowed by clomipramine and a melarsen oxide-trypanothione adduct (both are competitive inhibitors) but accelerated by quinacrine. The structure of the trypanothione reductase-quinacrine mustard adduct was determined to 2.7 Å, revealing two molecules of inhibitor bound in the trypanothione-binding site. The acridine moieties interact with each other through π-stacking effects, and one acridine interacts in a similar fashion with a tryptophan residue. These interactions provide a molecular explanation for the differing effects of clomipramine and quinacrine on inactivation by quinacrine mustard. Synergism with quinacrine occurs as a result of these planar acridines being able to stack together in the active site cleft, thereby gaining an increased number of binding interactions, whereas antagonism occurs with non-planar molecules, such as clomipramine, where stacking is not possible. PMID:15102853

  11. The three Mycobacterium tuberculosis antigen 85 isoforms have unique substrates and activities determined by non-active site regions.

    PubMed

    Backus, Keriann M; Dolan, Michael A; Barry, Conor S; Joe, Maju; McPhie, Peter; Boshoff, Helena I M; Lowary, Todd L; Davis, Benjamin G; Barry, Clifton E

    2014-09-05

    The three isoforms of antigen 85 (A, B, and C) are the most abundant secreted mycobacterial proteins and catalyze transesterification reactions that synthesize mycolated arabinogalactan, trehalose monomycolate (TMM), and trehalose dimycolate (TDM), important constituents of the outermost layer of the cellular envelope of Mycobacterium tuberculosis. These three enzymes are nearly identical at the active site and have therefore been postulated to exist to evade host immunity. Distal to the active site is a second putative carbohydrate-binding site of lower homology. Mutagenesis of the three isoforms at this second site affected both substrate selectivity and overall catalytic activity in vitro. Using synthetic and natural substrates, we show that these three enzymes exhibit unique selectivity; antigen 85A more efficiently mycolates TMM to form TDM, whereas C (and to a lesser extent B) has a higher rate of activity using free trehalose to form TMM. This difference in substrate selectivity extends to the hexasaccharide fragment of cell wall arabinan. Mutation of secondary site residues from the most active isoform (C) into those present in A or B partially interconverts this substrate selectivity. These experiments in combination with molecular dynamics simulations reveal that differences in the N-terminal helix α9, the adjacent Pro(216)-Phe(228) loop, and helix α5 are the likely cause of changes in activity and substrate selectivity. These differences explain the existence of three isoforms and will allow for future work in developing inhibitors.

  12. Fragment-based identification of determinants of conformational and spectroscopic change at the ricin active site

    SciTech Connect

    Carra,J.; McHugh, C.; Mulligan, S.; Machiesky, L.; Soares, A.; Millard, C.

    2007-01-01

    We found that amide ligands can bind weakly but specifically to the ricin active site, producing significant shifts in positions of the critical active site residues Arg180 and Tyr80. These results indicate that fragment-based drug discovery methods are capable of identifying minimal bonding determinants of active-site side-chain rearrangements and the mechanistic origins of spectroscopic shifts. Our results suggest that tryptophan fluorescence provides a sensitive probe for the geometric relationship of arginine-tryptophan pairs, which often have significant roles in protein function. Using the unusual characteristics of the RTA system, we measured the still controversial thermodynamic changes of site-specific urea binding to a protein, results that are relevant to understanding the physical mechanisms of protein denaturation.

  13. Structural and Kinetic Analyses of Macrophage Migration Inhibitory Factor Active Site Interactions

    SciTech Connect

    Crichlow, G.; Lubetsky, J; Leng, L; Bucala, R; Lolis, E

    2009-01-01

    Macrophage migration inhibitory factor (MIF) is a secreted protein expressed in numerous cell types that counters the antiinflammatory effects of glucocorticoids and has been implicated in sepsis, cancer, and certain autoimmune diseases. Interestingly, the structure of MIF contains a catalytic site resembling the tautomerase/isomerase sites of microbial enzymes. While bona fide physiological substrates remain unknown, model substrates have been identified. Selected compounds that bind in the tautomerase active site also inhibit biological functions of MIF. It had previously been shown that the acetaminophen metabolite, N-acetyl-p-benzoquinone imine (NAPQI), covalently binds to the active site of MIF. In this study, kinetic data indicate that NAPQI inhibits MIF both covalently and noncovalently. The structure of MIF cocrystallized with NAPQI reveals that the NAPQI has undergone a chemical alteration forming an acetaminophen dimer (bi-APAP) and binds noncovalently to MIF at the mouth of the active site. We also find that the commonly used protease inhibitor, phenylmethylsulfonyl fluoride (PMSF), forms a covalent complex with MIF and inhibits the tautomerase activity. Crystallographic analysis reveals the formation of a stable, novel covalent bond for PMSF between the catalytic nitrogen of the N-terminal proline and the sulfur of PMSF with complete, well-defined electron density in all three active sites of the MIF homotrimer. Conclusions are drawn from the structures of these two MIF-inhibitor complexes regarding the design of novel compounds that may provide more potent reversible and irreversible inhibition of MIF.

  14. All the catalytic active sites of MoS2 for hydrogen evolution

    SciTech Connect

    Li, Guoqing; Zhang, Du; Qiao, Qiao; Yu, Yifei; Peterson, David; Zafar, Abdullah; Kumar, Raj; Curtarolo, Stefano; Hunte, Frank; Shannon, Steve; Zhu, Yimei; Yang, Weitao; Cao, Linyou

    2016-11-29

    MoS2 presents a promising low-cost catalyst for the hydrogen evolution reaction (HER), but the understanding about its active sites has remained limited. Here we present an unambiguous study of the catalytic activities of all possible reaction sites of MoS2, including edge sites, sulfur vacancies, and grain boundaries. We demonstrate that, in addition to the well-known catalytically active edge sites, sulfur vacancies provide another major active site for the HER, while the catalytic activity of grain boundaries is much weaker. Here, the intrinsic turnover frequencies (Tafel slopes) of the edge sites, sulfur vacancies, and grain boundaries are estimated to be 7.5 s–1 (65–75 mV/dec), 3.2 s–1 (65–85 mV/dec), and 0.1 s–1 (120–160 mV/dec), respectively. We also demonstrate that the catalytic activity of sulfur vacancies strongly depends on the density of the vacancies and the local crystalline structure in proximity to the vacancies. Unlike edge sites, whose catalytic activity linearly depends on the length, sulfur vacancies show optimal catalytic activities when the vacancy density is in the range of 7–10%, and the number of sulfur vacancies in high crystalline quality MoS2 is higher than that in low crystalline quality MoS2, which may be related with the proximity of different local crystalline structures to the vacancies.

  15. Site-specific probabilistic seismic hazard analyses for the Idaho National Engineering Laboratory. Volume 1: Final report

    SciTech Connect

    1996-05-01

    This report describes and summarizes a probabilistic evaluation of ground motions for the Idaho National Engineering Laboratory (INEL). The purpose of this evaluation is to provide a basis for updating the seismic design criteria for the INEL. In this study, site-specific seismic hazard curves were developed for seven facility sites as prescribed by DOE Standards 1022-93 and 1023-96. These sites include the: Advanced Test Reactor (ATR); Argonne National Laboratory West (ANL); Idaho Chemical Processing Plant (ICPP or CPP); Power Burst Facility (PBF); Radioactive Waste Management Complex (RWMC); Naval Reactor Facility (NRF); and Test Area North (TAN). The results, probabilistic peak ground accelerations and uniform hazard spectra, contained in this report are not to be used for purposes of seismic design at INEL. A subsequent study will be performed to translate the results of this probabilistic seismic hazard analysis to site-specific seismic design values for the INEL as per the requirements of DOE Standard 1020-94. These site-specific seismic design values will be incorporated into the INEL Architectural and Engineering Standards.

  16. Using Carbohydrate Interaction Assays to Reveal Novel Binding Sites in Carbohydrate Active Enzymes

    PubMed Central

    Wilkens, Casper; Dilokpimol, Adiphol; Nakai, Hiroyuki; Lewińska, Anna; Abou Hachem, Maher; Svensson, Birte

    2016-01-01

    Carbohydrate active enzymes often contain auxiliary binding sites located either on independent domains termed carbohydrate binding modules (CBMs) or as so-called surface binding sites (SBSs) on the catalytic module at a certain distance from the active site. The SBSs are usually critical for the activity of their cognate enzyme, though they are not readily detected in the sequence of a protein, but normally require a crystal structure of a complex for their identification. A variety of methods, including affinity electrophoresis (AE), insoluble polysaccharide pulldown (IPP) and surface plasmon resonance (SPR) have been used to study auxiliary binding sites. These techniques are complementary as AE allows monitoring of binding to soluble polysaccharides, IPP to insoluble polysaccharides and SPR to oligosaccharides. Here we show that these methods are useful not only for analyzing known binding sites, but also for identifying new ones, even without structural data available. We further verify the chosen assays discriminate between known SBS/CBM containing enzymes and negative controls. Altogether 35 enzymes are screened for the presence of SBSs or CBMs and several novel binding sites are identified, including the first SBS ever reported in a cellulase. This work demonstrates that combinations of these methods can be used as a part of routine enzyme characterization to identify new binding sites and advance the study of SBSs and CBMs, allowing them to be detected in the absence of structural data. PMID:27504624

  17. Superfund Record of Decision (EPA Region 3): Harvey-Knott Drum site, New Castle County, Delaware, September 1985. Final report

    SciTech Connect

    Not Available

    1985-09-30

    The Harvey-Knott Drum Site is located in New Castle County, Delaware, approximately one-half mile east of the Maryland-Delaware border. The Harvey and Knotts Trucking, Inc., operated an open dump and burning ground on the site between 1963 and 1969. The facility accepted sanitary, municipal, and industrial wastes believed to be sludges, paint pigments, and solvents. Wastes were emptied onto the ground, into excavated trenches, or left in drums (some of which were buried). Some of these wastes were either burned as a means of reducing waste volume, or allowed to seep into the soil. Contamination of soil, surface water, and ground water has occurred as a result of disposal of these industrial wastes. The selected remedial action for this site is included.

  18. Technical procedures for water resources: Volume 3, Environmental Field Program, Deaf Smith County Site, Texas: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    To ensure that the environmental field program comprehensively addresses the issues and requirements of the project, a site study plan (SSP) has been prepared for Water Resources (ONWI, 1987). This technical procedure (TP) has been developed to implement the field program described in the Water Resources Site Study Plan. This procedure provides the general method for the field collection of water and sediment samples from playa lakes using an Alpha horizontal type sampler or equivalent or a peristaltic pump for water and a KB-coring devise or ponar grab for sediments. The samples will be preserved and then shipped to a laboratory for analysis. The water quality and sediment samples will be collected as part of the surface-water quality field study described in the Site Plan for Water Resources. 15 refs., 5 figs., 3 tabs.

  19. The hydrogen chemistry of the FeMo-co active site of nitrogenase.

    PubMed

    Dance, Ian

    2005-08-10

    The chemical mechanism by which nitrogenase enzymes catalyze the hydrogenation of N(2) (and other multiply bonded substrates) at the N(c)Fe(7)MoS(9)(homocitrate) active site (FeMo-co) is unknown, despite the accumulation of much data on enzyme reactivity and the influences of key amino acids surrounding FeMo-co. The mutual influences of H(2), substrates, and the inhibitor CO on reactivity are key experimental tests for postulated mechanisms. Fundamental to all aspects of mechanism is the accumulation of H atoms (from e(-) + H(+)) on FeMo-co, and the generation and influences of coordinated H(2). Here, I argue that the first introduction of H is via a water chain terminating at water 679 (PDB structure , Azotobacter vinelandii) to one of the mu(3)-S atoms (S3B) of FeMo-co. Next, using validated density functional calculations of a full chemical representation of FeMo-co and its connected residues (alpha-275(Cys), alpha-442(His)), I have characterized more than 80 possibilities for the coordination of up to three H atoms, and H(2), and H + H(2), on the S2A, Fe2, S2B, Fe6, S3B domain of FeMo-co, which is favored by recent targeted mutagenesis results. Included are calculated reaction profiles for movements of H atoms (between S and Fe, and between Fe and Fe), for the generation of Fe-H(2), for association and dissociation of Fe-H(2) at various reduction levels, and for H/H(2) exchange. This is new hydrogen chemistry on an unprecedented coordination frame, with some similarities to established hydrogen coordination chemistry, and with unexpected and unprecedented structures such as Fe(S)(3)(H(2))(2)(H) octahedral coordination. General principles for the hydrogen chemistry of FeMo-co include (1) the stereochemical mobility of H bound to mu(3)-S, (2) the differentiated endo- and exo- positions at Fe for coordination of H and/or H(2), and (3) coordinative allosteric influences in which structural and dynamic aspects of coordination at one Fe atom are affected by

  20. Formerly utilized MED/AEC sites remedial action program: radiological survey of the Building Site 421, United States, Watertown Arsenel, Watertown, MA. Final report

    SciTech Connect

    1980-02-01

    This report contains the results of surveys of the current radiological condition of the Building Site 421, United States Arsenal Watertown, Watertown, Massachusetts. Findings of this survey indicate there are four spots involving an area of less than 6000 cm/sup 2/ of identifiable low-level residual radioactivity on the concrete pad which is all that remains of Building Site 421. The largest spot is approximately 5000 cm/sup 2/. The other three spots are 100 cm/sup 2/ or less. The beta-gamma readings at these spots are 8.4 x 10/sup 2/ dis/min-100 cm/sup 2/, 2.2 x 10/sup 5/ dis/min-100 cm/sup 2/, 2.2 x 10/sup 5/ dis/min-100 cm/sup 2/ and 8.5 x 10/sup 4/ dis/min-100 cm/sup 2/. No alpha contamination was found at these locations. Gamma spectral analysis of a chip of contaminated concrete from one of the spots indicates that the contaminant is natural uranium. This contamination is fixed in the concrete and does not present an internal or external exposure hazard under present conditions. A hypothetical hazard analysis under a conservative set of assumed conditions indicates minimal internal hazard. The highest End Window contact reading was 0.09 mR/h. None of the other three spots indicated an elevated direct reading with the End Window Detector. Radon daughter concentrations were determined at three locations on the Building 421 pad. These were 0.00013 WL, 0.00011 WL and 0.00009 WL. According to the Surgeon General's Guidelines found in 10 CFR 712, radon daughter concentrations below 0.03 WL do not require remedial action in structures other than private dwellings and schools. Soil samples taken about the site indicate no elevated levels above the natural background levels in the soil. A gamma spectral analysis of a water sample obtained from the storm sewer line near the Building 421 pad indicates no elevated radioactivity in the sample. It was therefore felt that no contamination is present in this sewer.

  1. Georgia Tech Final Report Demonstration In Situ Plasma Vitrification Technology for Savannah River Site Contaminated Soils (U)

    SciTech Connect

    Schumacher, R.F.

    1996-12-01

    Previous experience with in-situ (Joule-heated) vitrification (ISV) of Savannah River site (SRS) highly weathered soil, has shown that the SRS soil is very refractory and a poor electrical conductor. These findings bring into question the likelihood of utilizing the Joule-heat type of vitrification treatment for waste sites and basins at SRS. An alternative approach may be in-situ plasma vitrification (ISPV). The ISPV approach provides a similar vitrified product and also has a safety advantage in that the melting is initiated at the bottom of a borehole compared to top-down melting for Joule heated ISV.

  2. Remedial action plan and site design for stabilization of the inactive uranium processing site at Naturita, Colorado. Appendix A of Attachment 3: Calculations, Final

    SciTech Connect

    Not Available

    1994-03-01

    This report contains calculations for: hydraulic gradients for Alluvial Aquifer and Salt Wash Aquifer; slug test analysis to determine hydraulic conductivity for Alluvial Aquifer and Salt Wash Aquifer; average linear groundwater velocity for Alluvial Aquifer and Salt Wash Aquifer; statistical analysis of the extent of existing groundwater contamination; hydraulic gradients for Dakota/Burro Canyon Formation and Salt Wash Aquifer; slug test analysis to determine hydraulic conductivity for Dakota/Burro Canyon Formation and Perched Salt Wash Aquifer; determination of hydraulic conductivity of the Dakota/Burro Canyon Formation from Packer Tests; average linear groundwater velocity for Dakota/Burro Canyon and Salt Wash Aquifer; chemical and mineralogical characterization of core samples from the Dry Flats Disposal Site; and demonstration of low groundwater yield from Uppermost Aquifer.

  3. Cyanide does more to inhibit heme enzymes, than merely serving as an active-site ligand

    SciTech Connect

    Parashar, Abhinav; Venkatachalam, Avanthika; Gideon, Daniel Andrew; Manoj, Kelath Murali

    2014-12-12

    Highlights: • Cyanide (CN) is a well-studied toxic principle, known to inhibit heme-enzymes. • Inhibition is supposed to result from CN binding at the active site as a ligand. • Diverse heme enzymes’ CN inhibition profiles challenge prevailing mechanism. • Poor binding efficiency of CN at low enzyme concentrations and ligand pressures. • CN-based diffusible radicals cause ‘non-productive electron transfers’ (inhibition). - Abstract: The toxicity of cyanide is hitherto attributed to its ability to bind to heme proteins’ active site and thereby inhibit their activity. It is shown herein that the long-held interpretation is inadequate to explain several observations in heme-enzyme reaction systems. Generation of cyanide-based diffusible radicals in heme-enzyme reaction milieu could shunt electron transfers (by non-active site processes), and thus be detrimental to the efficiency of oxidative outcomes.

  4. Synergistic effect between defect sites and functional groups on the hydrolysis of cellulose over activated carbon.

    PubMed

    Foo, Guo Shiou; Sievers, Carsten

    2015-02-01

    The chemical oxidation of activated carbon by H2 O2 and H2 SO4 is investigated, structural and chemical modifications are characterized, and the materials are used as catalysts for the hydrolysis of cellulose. Treatment with H2 O2 enlarges the pore size and imparts functional groups such as phenols, lactones, and carboxylic acids. H2 SO4 treatment targets the edges of carbon sheets primarily, and this effect is more pronounced with a higher temperature. Adsorption isotherms demonstrate that the adsorption of oligomers on functionalized carbon is dominated by van der Waals forces. The materials treated chemically are active for the hydrolysis of cellulose despite the relative weakness of most of their acid sites. It is proposed that a synergistic effect between defect sites and functional groups enhances the activity by inducing a conformational change in the glucan chains if they are adsorbed at defect sites. This activates the glycosidic bonds for hydrolysis by in-plane functional groups.

  5. Denaturation studies of active-site labeled papain using electron paramagnetic resonance and fluorescence spectroscopy.

    PubMed Central

    Ping, Z A; Butterfiel, D A

    1991-01-01

    A spin-labeled p-chloromercuribenzoate (SL-PMB) and a fluorescence probe, 6-acryloyl-2-dimethylaminonaphthalene (Acrylodan), both of which bind to the single SH group located in the active site of papain, were used to investigate the interaction of papain (EC 3.4.22.2) with two protein denaturants. It was found that the active site of papain was highly stable in urea solution, but underwent a large conformational change in guanidine hydrochloride solution. Electron paramagnetic resonance and fluorescence results were in agreement and both paralleled enzymatic activity of papain with respect to both the variation in pH and denaturation. These results strongly suggest that SL-PMB and Acrylodan labels can be used to characterize the physical state of the active site of the enzyme. PMID:1657229

  6. Enhancement of Polymerase Activity of the Large Fragment in DNA Polymerase I from Geobacillus stearothermophilus by Site-Directed Mutagenesis at the Active Site

    PubMed Central

    Ma, Yi; Zhang, Beilei; Wang, Meng; Ou, Yanghui

    2016-01-01

    The large fragment of DNA polymerase I from Geobacillus stearothermophilus GIM1.543 (Bst DNA polymerase) with 5′-3′ DNA polymerase activity while in absence of 5′-3′ exonuclease activity possesses high thermal stability and polymerase activity. Bst DNA polymerase was employed in isothermal multiple self-matching initiated amplification (IMSA) which amplified the interest sequence with high selectivity and was widely applied in the rapid detection of human epidemic diseases. However, the detailed information of commercial Bst DNA polymerase is unpublished and well protected by patents, which makes the high price of commercial kits. In this study, wild-type Bst DNA polymerase (WT) and substitution mutations for improving the efficiency of DNA polymerization were expressed and purified in E. coli. Site-directed substitutions of four conserved residues (Gly310, Arg412, Lys416, and Asp540) in the activity site of Bst DNA polymerase influenced efficiency of polymerizing dNTPs. The substitution of residue Gly310 by alanine or leucine and residue Asp540 by glutamic acid increased the efficiency of polymerase activity. All mutants with higher polymerizing efficiency were employed to complete the rapid detection of EV71-associated hand, foot, and mouth disease (HFMD) by IMSA approach with relatively shorter period which is suitable for the primary diagnostics setting in rural and underdeveloped areas. PMID:27981047

  7. Superfund Record of Decision (EPA Region 4): Tower Chemical Company Site, Clermont, Florida, July 1987. Final report

    SciTech Connect

    Not Available

    1987-07-09

    The Tower Chemical Company (TCC) site is an abandoned manufacturing facility located along the eastern edge of Lake County, Florida. The TCC owned and utilized two separate parcels of land: a main facility and a spray-irrigation field. Approximately 16 residences, located within a 1.2-mile radius of the site, tap the underlying aquifer for their water supply. Wetlands and swamps are also nearby the site. From 1957 to 1981, the TCC manufactured, formulated and stored various pesticides. Acidic wastewaters, produced during the manufacturing process were discharged into the unlined percolation/evaporation pond located at the main facility. In July 1980, the pond overflowed and discharge was diverted to the spray irrigation field. In June 1980, as a result of damages caused by the wastewater pond overflow, the Florida Department of Environmental Regulation (FDER) ordered TCC to cease all discharges from the site studies, initiated by both EPA and FDER, indicated high concentrations of DDT and associated pesticide compounds in the main facility and a below normal fish population in the unnamed stream onsite.

  8. Superfund Record of Decision (EPA Region 3): Douglassville Disposal Site, Berks County, Pennsylvania, September 1985. Final report

    SciTech Connect

    Not Available

    1985-09-27

    The Douglassville Disposal Site occupies approximately 50 acres of land along the southern bank of the Schuylkill River in southeastern Berks County, Union Township, Pennsylvania. Site operations included lubricating-oil recycling in 1941 and waste solvents recycling in the 1950's and 1960's. Wastes generated from these operations were stored in several lagoons located in the northern half of the site until 1972. In November 1970, ten days of heavy rain caused the lagoons to overflow and breach safety dikes releasing 2-3 million gallons of wastes. The dikes were repaired and a Federal decree was issued stating that no more waste material was to be stored in the lagoons. Actions were also initiated to dispose of remaining waste materials. Before the action could be carried out, tropical storm Agnes caused the Schuylkill River to overflow its banks and inundate the entire site. An estimated 6 to 8 million gallons of wastes were released and carried downstream by floodwaters for about 15 miles.

  9. Subsurface stratigraphy and structure of A/M area at the Savannah River Site, Aiken County, South Carolina. Final report

    SciTech Connect

    Fallaw, W.C.; Sims, W.R.; Haselow, J.S.

    1991-08-01

    This report is a study of the stratigraphy and structure of the A/M Area Hazardous Waste Management Facility Post-Closure Care Permit process on the Savannah River Site. The data from the lithologic and geophysical logs of 93 wells is the basis of this analysis.

  10. Comment and response document for the final long-term surveillance plan for the Green River, Utah, disposal site

    SciTech Connect

    Not Available

    1994-08-01

    This document contains comments made by the U.S. Nuclear Regulatory Commission addressing their concerns over the long-term monitoring program for the Green River Disposal Site, UMTRA project. Responses are included as well as plans for implementation of changes, if any are deemed necessary.

  11. Development of red oak seedlings using plastic shelters on hardwood sites in West Virginia. Forest Service research paper (Final)

    SciTech Connect

    Smith, H.C.

    1993-04-01

    Plastic shelters were used to grow red oak seedlings on good-to-excellent Appalachian hardwood growing sites in north central West Virginia. Preliminary results indicate that shelters have the potential to stimulate development of red oak seedlingheight growth, especially if height growth continues once the seedling tops are above the 5-foot-tall shelters.

  12. Tooele Army Depot Revised Final Site-Wide Ecological Risk Assessment. Volume II (Appendices A through D).

    DTIC Science & Technology

    1998-02-01

    Chemical Quality Control - TEAD-N Ecological Risk Assesment Soils Data (All Rinse Blanks) SUe ID Test Name Meas Flag Unit Bool Ceae Value...Ecological 1 lisk Assesment boils D ata (All Rinse Blanks) RaveBiau\\ Meas Flat Unit Flat !*■** Meas Site ID Test Name Bool Ceae

  13. Multi-site magnetotelluric measurement system with real-time data analysis. Final technical report No. 210

    SciTech Connect

    Becker, J.D.; Bostick, F.X. Jr.; Smith, H.W.

    1981-09-01

    A magnetotelluric measurement system has been designed to provide a more cost effective electrical method for geothermal and mineral exploration. The theoretical requirements and sensitivities of the magnetotelluric inversion process were specifically addressed in determining system performance requirements. Significantly reduced instrument noise levels provide improved data quality, and simultaneous measurement at up to six locations provides reduced cost per site. Remotely located, battery powered, instrumentation packages return data to a central controlling site through a 2560 baud wire-line or radio link. Each remote package contains preamplifiers, data conditioning filters, and a 12-bit gain ranging A-D converter for frequencies from 0.001 Hz to 8 Hz. Data frequencies above 8 Hz are processed sequentially by a heterodyne receiver to reduce bandwidth to within the limits of the 2560 baud data link. The central data collection site provides overall control for the entire system. The system operator interacts with the system through a CRT terminal, and he receives hard copy from a matrix graphics printer. Data from the remote packages may be recorded in time sequence on a magnetic tape cartridge system, or an optional Hewlett-Packard 21MX minicomputer can be used to perform real-time frequency analysis. The results of this analysis provide feedback to the operator for improved evaluation of system performance and for selection of future measurement sites.

  14. Technical procedures for water resources: Volume 4, Deaf Smith County site, Texas: Environmental Field Program: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    This volume contains Technical Procedures pursuant to the water Resources Site Study Plan: including Collection, Preservation, and Shipment of Ground-Water Samples; Inventory Current Water Use and Estimating Projected Water Use; Estimation of Precipitation Depth, Duration, Frequence; Estimation of Probable Maximum Precipitation; Calculation of Floodplains.

  15. Technical procedures for water resources, Deaf Smith County site, Texas: Volume 1: Environmental Field Program: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    This volume contains Technical Procedures pursuant to the Water Resources Site Study Plan including, determination of basin topographic characteristics, determination of channel and playa lake characteristics, operation of a stream gaging station, operation of a playa lake stage gaging system, and processing of data from a playa lake stage gaging system.

  16. Disposal of chemical agents and munitions stored at Umatilla Depot Activity, Hermiston, Oregon. Final Phase 1 environmental report

    SciTech Connect

    Zimmerman, G.P.; Hillsman, E.L.; Johnson, R.O.; Miller, R.L.; Patton, T.G.; Schoepfle, G.M.; Tolbert, V.R.; Feldman, D.L.; Hunsaker, D.B. Jr.; Kroodsma, R.L.; Morrissey, J.; Rickert, L.W.; Staub, W.P.; West, D.C.

    1993-02-01

    The Umatilla Depot Activity (UMDA) near Hermiston, Oregon, is one of eight US Army installations in the continental United States where lethal unitary chemical agents and munitions are stored, and where destruction of agents and munitions is proposed under the Chemical Stockpile Disposal Program (CSDP). The chemical agent inventory at UMDA consists of 11.6%, by weight, of the total US stockpile. The destruction of the stockpile is necessary to eliminate the risk to the public from continued storage and to dispose of obsolete and leaking munitions. In 1988 the US Army issued a Final Programmatic Environmental Impact Statement (FPEIS) for the CSDP that identified on-site disposal of agents and munitions as the environmentally preferred alternative (i.e., the alternative with the least potential to cause significant adverse impacts), using a method based on five measures of risk for potential human health and ecosystem/environmental effects; the effectiveness and adequacy of emergency preparedness capabilities also played a key role in the FPEIS selection methodology. In some instances, the FPEIS included generic data and assumptions that were developed to allow a consistent comparison of potential impacts among programmatic alternatives and did not include detailed conditions at each of the eight installations. The purpose of this Phase 1 report is to examine the proposed implementation of on-site disposal at UMDA in light of more recent and more detailed data than those included in the FPEIS. Specifically, this Phase 1 report is intended to either confirm or reject the validity of on-site disposal for the UMDA stockpile. Using the same computation methods as in the FPEIS, new population data were used to compute potential fatalities from hypothetical disposal accidents. Results indicate that onsite disposal is clearly preferable to either continued storage at UMDA or transportation of the UMDA stockpile to another depot for disposal.

  17. In silico analysis of Pycnoporus cinnabarinus laccase active site with toxic industrial dyes.

    PubMed

    Prasad, Nirmal K; Vindal, Vaibhav; Narayana, Siva Lakshmi; Ramakrishna, V; Kunal, Swaraj Priyaranjan; Srinivas, M

    2012-05-01

    Laccases belong to multicopper oxidases, a widespread class of enzymes implicated in many oxidative functions in various industrial oxidative processes like production of fine chemicals to bioremediation of contaminated soil and water. In order to understand the mechanisms of substrate binding and interaction between substrates and Pycnoporus cinnabarinus laccase, a homology model was generated. The resulted model was further validated and used for docking studies with toxic industrial dyes- acid blue 74, reactive black 5 and reactive blue 19. Interactions of chemical mediators with the laccase was also examined. The docking analysis showed that the active site always cannot accommodate the dye molecules, due to constricted nature of the active site pocket and steric hindrance of the residues whereas mediators are relatively small and can easily be accommodated into the active site pocket, which, thereafter leads to the productive binding. The binding properties of these compounds along with identification of critical active site residues can be used for further site-directed mutagenesis experiments in order to identify their role in activity and substrate specificity, ultimately leading to improved mutants for degradation of these toxic compounds.

  18. Conformational Change in the Active Site of Streptococcal Unsaturated Glucuronyl Hydrolase Through Site-Directed Mutagenesis at Asp-115.

    PubMed

    Nakamichi, Yusuke; Oiki, Sayoko; Mikami, Bunzo; Murata, Kousaku; Hashimoto, Wataru

    2016-08-01

    Bacterial unsaturated glucuronyl hydrolase (UGL) degrades unsaturated disaccharides generated from mammalian extracellular matrices, glycosaminoglycans, by polysaccharide lyases. Two Asp residues, Asp-115 and Asp-175 of Streptococcus agalactiae UGL (SagUGL), are completely conserved in other bacterial UGLs, one of which (Asp-175 of SagUGL) acts as a general acid and base catalyst. The other Asp (Asp-115 of SagUGL) also affects the enzyme activity, although its role in the enzyme reaction has not been well understood. Here, we show substitution of Asp-115 in SagUGL with Asn caused a conformational change in the active site. Tertiary structures of SagUGL mutants D115N and D115N/K370S with negligible enzyme activity were determined at 2.00 and 1.79 Å resolution, respectively, by X-ray crystallography. The side chain of Asn-115 is drastically shifted in both mutants owing to the interaction with several residues, including Asp-175, by formation of hydrogen bonds. This interaction between Asn-115 and Asp-175 probably prevents the mutants from triggering the enzyme reaction using Asp-175 as an acid catalyst.

  19. Substrate shuttling between active sites of uroporphyrinogen decarboxylase is not required to generate coproporphyrinogen

    PubMed Central

    Phillips, John D.; Warby, Christy A.; Whitby, Frank G.; Kushner, James P.; Hill, Christopher P.

    2009-01-01

    Summary Uroporphyrinogen Decarboxylase (URO-D; EC 4.1.1.37), the fifth enzyme of the heme biosynthetic pathway, is required for the production of heme, vitamin B12, siroheme, and chlorophyll precursors. URO-D catalyzes the sequential decarboxylation of the four acetate side chains on the pyrrole groups of uroporphyrinogen to produce coproporphyrinogen. URO-D is a stable homodimer with the active site clefts of the two subunits adjacent to each other. It has been hypothesized that the two catalytic centers interact functionally, perhaps by shuttling of reaction intermediates between subunits. We tested this hypothesis by construction of a single chain protein (scURO-D) in which the two subunits were connected by a flexible linker. The crystal structure of this protein was shown to be superimposible with wild-type activity and have comparable catalytic activity. Mutations that impaired one or the other of the two active sites of scURO-D resulted in approximately half of wild-type activity. The distribution of reaction intermediates was the same for mutant and wild-type sequences, and was unaltered in a competition experiment using the I and III isomer substrates. These observations indicate that communication between active sites is not required for enzyme function, and suggest that the dimeric structure of URO-D is required to achieve conformational stability and create a large active site cleft. PMID:19362562

  20. Substrate Shuttling Between Active Sites of Uroporphyrinogen Decarboxylase in Not Required to Generate Coproporphyrinogen

    SciTech Connect

    Phillips, J.; Warby, C; Whitby, F; Kushner, J; Hill, C

    2009-01-01

    Uroporphyrinogen decarboxylase (URO-D; EC 4.1.1.37), the fifth enzyme of the heme biosynthetic pathway, is required for the production of heme, vitamin B12, siroheme, and chlorophyll precursors. URO-D catalyzes the sequential decarboxylation of four acetate side chains in the pyrrole groups of uroporphyrinogen to produce coproporphyrinogen. URO-D is a stable homodimer, with the active-site clefts of the two subunits adjacent to each other. It has been hypothesized that the two catalytic centers interact functionally, perhaps by shuttling of reaction intermediates between subunits. We tested this hypothesis by construction of a single-chain protein (single-chain URO-D) in which the two subunits were connected by a flexible linker. The crystal structure of this protein was shown to be superimposable with wild-type activity and to have comparable catalytic activity. Mutations that impaired one or the other of the two active sites of single-chain URO-D resulted in approximately half of wild-type activity. The distributions of reaction intermediates were the same for mutant and wild-type sequences and were unaltered in a competition experiment using I and III isomer substrates. These observations indicate that communication between active sites is not required for enzyme function and suggest that the dimeric structure of URO-D is required to achieve conformational stability and to create a large active-site cleft.

  1. Crystal structure of an avian influenza polymerase PA[subscript N] reveals an endonuclease active site

    SciTech Connect

    Yuan, Puwei; Bartlam, Mark; Lou, Zhiyong; Chen, Shoudeng; Zhou, Jie; He, Xiaojing; Lv, Zongyang; Ge, Ruowen; Li, Xuemei; Deng, Tao; Fodor, Ervin; Rao, Zihe; Liu, Yingfang

    2009-11-10

    The heterotrimeric influenza virus polymerase, containing the PA, PB1 and PB2 proteins, catalyses viral RNA replication and transcription in the nucleus of infected cells. PB1 holds the polymerase active site and reportedly harbours endonuclease activity, whereas PB2 is responsible for cap binding. The PA amino terminus is understood to be the major functional part of the PA protein and has been implicated in several roles, including endonuclease and protease activities as well as viral RNA/complementary RNA promoter binding. Here we report the 2.2 angstrom (A) crystal structure of the N-terminal 197 residues of PA, termed PA(N), from an avian influenza H5N1 virus. The PA(N) structure has an alpha/beta architecture and reveals a bound magnesium ion coordinated by a motif similar to the (P)DX(N)(D/E)XK motif characteristic of many endonucleases. Structural comparisons and mutagenesis analysis of the motif identified in PA(N) provide further evidence that PA(N) holds an endonuclease active site. Furthermore, functional analysis with in vivo ribonucleoprotein reconstitution and direct in vitro endonuclease assays strongly suggest that PA(N) holds the endonuclease active site and has critical roles in endonuclease activity of the influenza virus polymerase, rather than PB1. The high conservation of this endonuclease active site among influenza strains indicates that PA(N) is an important target for the design of new anti-influenza therapeutics.

  2. Transcriptional activation by LR1 at the Eµ enhancer and switch region sites

    PubMed Central

    Hanakahi, L. A.; Maizels, Nancy

    2000-01-01

    LR1 is a B cell-specific, sequence-specific duplex DNA binding activity which is induced in B cells carrying out class switch recombination. Here we identify several properties of LR1 which enable it to function in transcriptional regulation. We show that LR1 contributes to transcriptional activation by the Eµ immunoglobulin heavy chain intron enhancer by binding to a site within the enhancer core. We further show that LR1 bends DNA upon binding. In addition, we show that LR1 is itself a bona fide transcriptional activator, as multimerized LR1 sites produce an element which can enhance transcription from a minimal promoter. In order for class switch recombination to occur, an activating signal must be transmitted via the Eµ core, and both S regions targeted for recombination must be actively transcribed. The properties of LR1 that we have identified suggest distinct potential functions of LR1 duplex DNA binding activity in class switch recombination. First, LR1 may contribute to recombinational activation by the Eµ core. Second, there are multiple potential LR1 duplex binding sites in each of the G-rich switch regions, and LR1 bound at contiguous sites may enhance recombination by stimulating transcription of the S regions. PMID:10908319

  3. Record of principal work activities/deliverables. Final technical report, September 28, 1984--September 27, 1989

    SciTech Connect

    Not Available

    1989-09-01

    Over the five year period of performance, thirteen task assignments were issued by the DOE to ARINC Research. During the two year base period seven tasks were assigned. Two task assignments were issued for each of the three consecutive one year option periods. Associated with all task assignments were multiple subtasks, some of which required significant effort. These subtasks are appropriately cited in this report under their respective task assignments as principal work activities or deliverables. The technical and management support provided to the DOE under this contract focused on two general areas: (1) appraisal activities and (2) non-appraisal activities. Support to appraisals included planning, document review, developing lines-of-inquiry, interviewing, data collection, report writing, and follow-up. Such work was executed both on-site at the DOE facility under review and off-site. Non-appraisal support was varied and included such areas as document review, data base development, technical assessments. statistical analysis, policy analysis, reliability engineering, and workshop and conference planning and execution.

  4. Regulation of Dpp activity by tissue-specific cleavage of an upstream site within the prodomain

    PubMed Central

    Sopory, Shailaja; Kwon, Sunjong; Wehrli, Marcel; Christian, Jan L.

    2010-01-01

    BMP4 is synthesized as an inactive precursor that is cleaved at two sites during maturation: initially at a site (S1) adjacent to the ligand domain, and then at an upstream site (S2) within the prodomain. Cleavage at the second site regulates the stability of mature BMP4 and this in turn influences its signaling intensity and range of action. The Drosophila ortholog of BMP4, Dpp, functions as a long- or short-range signaling molecule in the wing disc or embryonic midgut, respectively but mechanisms that differentially regulate its bioactivity in these tissues have not been explored. In the current studies we demonstrate, by dpp mutant rescue, that cleavage at the S2 site of proDpp is required for development of the wing and leg imaginal discs, whereas cleavage at the S1 site is sufficient to rescue Dpp function in the midgut. Both the S1 and S2 site of proDpp are cleaved in the wing disc, and S2-cleavage is essential to generate sufficient ligand to exceed the threshold for pMAD activation at both short- and long-range in most cells. By contrast, proDpp is cleaved at the S1 site alone in the embryonic mesoderm and this generates sufficient ligand to activate physiological target genes in neighboring cells. These studies provide the first biochemical and genetic evidence that that selective cleavage of the S2 site of proDPP provides a tissue-specific mechanism for regulating Dpp activity, and that differential cleavage can contribute to, but is not an absolute determinant of signaling range. PMID:20659445

  5. Multiple active site residues are important for photochemical efficiency in the light-activated enzyme protochlorophyllide oxidoreductase (POR).

    PubMed

    Menon, Binuraj R K; Hardman, Samantha J O; Scrutton, Nigel S; Heyes, Derren J

    2016-08-01

    Protochlorophyllide oxidoreductase (POR) catalyzes the light-driven reduction of protochlorophyllide (Pchlide), an essential, regulatory step in chlorophyll biosynthesis. The unique requirement of the enzyme for light has provided the opportunity to investigate how light energy can be harnessed to power biological catalysis and enzyme dynamics. Excited state interactions between the Pchlide molecule and the protein are known to drive the subsequent reaction chemistry. However, the structural features of POR and active site residues that are important for photochemistry and catalysis are currently unknown, because there is no crystal structure for POR. Here, we have used static and time-resolved spectroscopic measurements of a number of active site variants to study the role of a number of residues, which are located in the proposed NADPH/Pchlide binding site based on previous homology models, in the reaction mechanism of POR. Our findings, which are interpreted in the context of a new improved structural model, have identified several residues that are predicted to interact with the coenzyme or substrate. Several of the POR variants have a profound effect on the photochemistry, suggesting that multiple residues are important in stabilizing the excited state required for catalysis. Our work offers insight into how the POR active site geometry is finely tuned by multiple active site residues to support enzyme-mediated photochemistry and reduction of Pchlide, both of which are crucial to the existence of life on Earth.

  6. An Electromagnetic Interference Study of Potential Transmitter Sites for the HF Active Auroral Research Program (HAARP)

    DTIC Science & Technology

    1993-07-19

    heating . The measurements described in this report were conducted at a number of candidate HAARP transmitter sites in the vicinity of Fairbanks...employ the High Power Auroral Stimulation (HIPAS) RF heating facility [1], located in the Chena River valley area near Fairbanks. HAARP will be an...Potential Transmitter Sites for the HF Active Auroral Research Program ( HAARP ) JOSEP11 A. GOLDSTEIN EDWARD 1. KENNEDY ADRIAN S. ELEY 4 IMICHlAEL A. RuPAR C

  7. Probing the catalytic mechanism of bovine CD38/NAD+ glycohydrolase by site directed mutagenesis of key active site residues.

    PubMed

    Kuhn, Isabelle; Kellenberger, Esther; Cakir-Kiefer, Céline; Muller-Steffner, Hélène; Schuber, Francis

    2014-07-01

    Bovine CD38/NAD(+) glycohydrolase catalyzes the hydrolysis of NAD(+) to nicotinamide and ADP-ribose and the formation of cyclic ADP-ribose via a stepwise reaction mechanism. Our recent crystallographic study of its Michaelis complex and covalently-trapped intermediates provided insights into the modalities of substrate binding and the molecular mechanism of bCD38. The aim of the present work was to determine the precise role of key conserved active site residues (Trp118, Glu138, Asp147, Trp181 and Glu218) by focusing mainly on the cleavage of the nicotinamide-ribosyl bond. We analyzed the kinetic parameters of mutants of these residues which reside within the bCD38 subdomain in the vicinity of the scissile bond of bound NAD(+). To address the reaction mechanism we also performed chemical rescue experiments with neutral (methanol) and ionic (azide, formate) nucleophiles. The crucial role of Glu218, which orients the substrate for cleavage by interacting with the N-ribosyl 2'-OH group of NAD(+), was highlighted. This contribution to catalysis accounts for almost half of the reaction energy barrier. Other contributions can be ascribed notably to Glu138 and Asp147 via ground-state destabilization and desolvation in the vicinity of the scissile bond. Key interactions with Trp118 and Trp181 were also proven to stabilize the ribooxocarbenium ion-like transition state. Altogether we propose that, as an alternative to a covalent acylal reaction intermediate with Glu218, catalysis by bCD38 proceeds through the formation of a discrete and transient ribooxocarbenium intermediate which is stabilized within the active site mostly by electrostatic interactions.

  8. Remedial Action Plan and site design for stabilization of the inactive uranium mill tailings site at Gunnison, Colorado. Attachment 5, Supplemental radiological data: Final report

    SciTech Connect

    Not Available

    1992-10-01

    Diffusion coefficients for radon gas in earthen materials are required to design suitable radon-barrier covers for uranium tailings impoundments and other materials that emit radon gas. Many early measurements of radon diffusion coefficients relied on the differences in steady-state radon fluxes measured from radon source before and after installation of a cover layer of the material being tested. More recent measurements have utilized the small-sample transient (SST) technique for greater control on moistures and densities of the test soils, greater measurement precision, and reduced testing time and costs. Several of the project sites for the US Department of Energy`s Uranium Mill Tailings Remedial Action (UMTRA) Program contain radiologically contaminated subsurface material composed predominantly of cobbles, gravels andsands. Since remedial action designs require radon diffusion coefficients for the source materials as well as the cover materials, these cobbly and gravelly materials also must be tested. This report contains the following information: a description of the test materials used and the methods developed to conduct the SST radon diffusion measurements on cobbly soils; the protocol for conducting radon diffusion tests oncobbly soils; the results of measurements on the test samples; and modifications to the FITS computer code for analyzing the time-dependent radon diffusion data.

  9. Probe molecule studies: Active species in alcohol synthesis. Final report, July 1993--July 1994

    SciTech Connect

    Blackmond, D.G.; Wender, I.; Oukaci, R.; Wang, Jian

    1994-07-01

    The objectives of this project are to investigate the role(s) of cobalt and copper in constructing the active sites for the formation of higher alcohols from CO/H{sub 2} over the Co-Cu based catalysts by using different reduction treatments and applying selected characterization tools such as TPR, TPD, XRD and XPS as well as to generate mechanistic information on the reaction pathway(s) and key intermediate(s) of higher alcohol synthesis from CO/H{sub 2} over Co-Cu/ZnO catalysts by the approach of in-situ addition of a probe molecule (nitromethane).

  10. Superfund Record of Decision (EPA Region 6): North Cavalcade Street site, Houston, Texas (first remedial action), June 1988. Final report

    SciTech Connect

    Not Available

    1988-06-28

    The 21-acre North Cavalcade site is located in northeast Houston, Texas. The surrounding areas are a mixture of residential, commercial, and industrial properties. Surface water is drained by three stormwater drainage ditches, a limited aquatic habitat as classified by Texas Water Quality Standards. The site was developed in 1946 when Houston Creosoting Company, Inc. (HCCI) established creosote wood-preserving operations. Around 1955, HCCI added pentachlorophenol (PCP), wood-preservation services, and other support facilities. The area of soil contamination corresponds to where creosote was historically stored, and the point of entry for the contaminants into the ground water. The primary contaminants of concerning affecting the ground water, soils, and sediments include: VOCs, benzene, toluene, xylene, and PAHs.

  11. Interrelation of technologies for RW preparation and sites for final isolation of the wastes from pyrochemical processing of SNF

    SciTech Connect

    Gupalo, V.S.; Chistyakov, V.N.; Kormilitsyn, M.V.; Kormilitsyna, L.A.

    2013-07-01

    For the justification of engineering solutions and practical testing of the radiochemical component of the perspective nuclear power complex with on-site variant of nuclear fuel cycle (NFC), it is planned to establish a multi-functional research-development complex (MFCRC) for radiochemical processing of spent nuclear fuels (SNF) from fast reactors. MFCRC is being established at the NIIAR site, it comprises technological process lines, where innovation pyro-electrochemical and hydrometallurgical technologies are realized, with an option for closing the inter-chain material flows for testing the combined radiochemically converted materials. The technological flowchart for processing at the MFCRC is subdivided into 3 segments: -) complex of the lead operations for dismantling the fuel elements (FE) and fuel assemblies (FA), -) pyrochemical extraction flowchart for processing SNF, and -) hydrometallurgical flowchart for processing SNF. The engineered solutions for the management and disposition of the radioactive wastes from MFCRC are reviewed.

  12. Surface and subsurface cleanup protocol for radionuclides Gunnison, Colorado, UMTRA Project Processing Site. Revision 3, Final report

    SciTech Connect

    Not Available

    1994-05-01

    The supplemental standards provisions of Title 40, Code of Federal Regulations, Part 192 (40 CFR Part 192) require the cleanup of radionuclides other than radium-226 (Ra-226) to levels ``as low as reasonably achievable`` (ALARA), taking into account site-specific conditions, if sufficient quantities and concentrations are present to constitute a significant radiation hazard. In this context, thorium-230 (Th-230) at the Gunnison, Colorado, processing site will require remediation. However, a seasonally fluctuating groundwater table at the site significantly complicates conventional remedial action with respect to cleanup. Characterization data indicate that in the offpile areas, the removal of residual in situ bulk Ra-226 and Th-230 such that the 1000-year projected Ra-226 concentration (Ra-226 concentration in 1000 years due to the decay of in situ Ra-226 and the in-growth of Ra-226 from in situ Th-230) complies with the US Environmental Protection Agency (EPA) cleanup standard for in situ Ra-226 and the cleanup protocol for in situ Th-230 can be readily achieved using conventional excavation techniques for bulk contamination without encountering significant impacts due to groundwater. The EPA cleanup standard and criterion for Ra-226 and the 1000-year projected Ra-226 are 5 and 15 picocuries per gram (pCi/g) above background, respectively, averaged over 15-centimeter (cm) deep surface and subsurface intervals and 100-square-meter (m{sup 2}) grid areas. Significant differential migration of Th-230 relative to Ra-226 has occurred over 40 percent of the subpile area. To effectively remediate the site with respect to Ra-226 and Th-230, supplemental standard is proposed and discussed in this report.

  13. Fort Dix Remedial Investigation/Feasibility Study for 13 Sites, Final Technical Plan, Data Item A004

    DTIC Science & Technology

    1995-09-01

    four deep wells, drilled with mud rotary 26 techniques, to assist in defining the geologic setting. 27 28 The remaining four shallow (water table...included to assist in development of the FS. During groundwater sampling, a complete round of groundwater level measurements will be taken from all...4 flow system and provide a mathematical framework for describing contaminant 5 distribution and migration at this site. Overall, this will assist

  14. West Hackberry Strategic Petroleum Reserve site brine-disposal monitoring, Year I report. Volume III. Biological oceanography. Final report

    SciTech Connect

    DeRouen, L.R.; Hann, R.W.; Casserly, D.M.; Giammona, C.; Lascara, V.J.

    1983-02-01

    The Department of Energy's Strategic Petroleum Reserve Program began discharging brine into the Gulf of Mexico from its West Hackberry site near Cameron, Louisiana in May 1981. The brine originates from underground salt domes being leached with water from the Intracoastal Waterway, making available vast underground storage caverns for crude oil. The effects of brine discharge on aquatic organisms are presented in this volume. The topics covered are: benthos; nekton; phytoplankton; zooplankton; and data management.

  15. Efficient on-site degradation of high concentration of spent deicing fluids: A laboratory study. Final report

    SciTech Connect

    Strong, J.M.; Waltz, M.

    1997-10-01

    The on-site treatment of antifreeze compounds and aircraft deicing fluids (ethylene glycol and propylene glycol) will reduce disposal costs, decrease environmental impact, minimize the potential for additional spills/contamination and meet the goals of pollution prevention by reducing the amount of hazardous materials generated. The authors have identified bacteria that can degrade 1-10% glycol waste at room temperatures of ca. 23C. A second subculture was isolated that could degrade glycol waste at ca. 4C.

  16. TTP AL921102: An integrated geophysics program for non-intrusive characterization of mixed-Waste landfill sites. Final report

    SciTech Connect

    Hasbrouck, J.C.

    1993-09-01

    This Technical Task conducted for the US Department of Energy Office of Technology Development demonstrates the effectiveness of integrating several surface geophysical techniques to nonintrusively characterize mixed-waste landfill sites. An integrated approach enables an area to be characterized faster and cheaper because repeated access is not necessary and offers data and interpretations not attainable by a single technique. Field demonstrations using the complex galvanic resistivity, spontaneous potential (SP), ground-penetrating radar (GPR), time-domain electromagnetic (TDEM), shear-wave (S-wave) seismic and compressional-wave (P-wave) seismic geophysical techniques were conducted at the Mixed-Waste Landfill Integrated Demonstration (MWLID) test site at the Sandia National Laboratories/New Mexico in Albuquerque. Data were acquired in two areas that have both known and unknown attributes. Although data from numerous profiles were analyzed, three lines were chosen as representative of the landfill site: Line 20E that crosses both the known Chromic Acid and Organics Pits, Line 60E that transectes an essentially barren area, and Line 125E located in an area with unknown subsurface conditions.

  17. Superfund Record of Decision (EPA Region 1): Cannon's Engineering Corporation (CEC) Plymouth Site, Plymouth, Massachusetts, September 1985. Final report

    SciTech Connect

    Not Available

    1985-09-30

    The Cannon Engineering Corporation (CEC) Plymouth Site is located in Cordage Park, a business and industrial park bordering Plymouth Harbor, in Plymouth, Massachusetts. The site consists of 2.5 acres which includes three above-ground storage tanks, two of which are estimated to have nominal storage capacities in excess of 250,000 gallons each, and one which has an estimated 500,000-gallon capacity. The tanks were originally used for the storage of 6 marine fuel oil and bunker C oil. In 1976, CEC rented one tank for the reported storage of waste oil and later rented a second tank. Allegedly, CEC used the tanks to store hazardous wastes. In 1979, CEC was licensed by the Massachusetts Department of Environmental Quality Engineering (DEOE) to store motor oils, industrial oils and emulsions, solvents, laquers, organic chemicals, inorganic chemicals, cyanide and plating waste, clay and filter media containing chemicals, plating sludge, oily solids and pesticides. Potential problems observed at the site included slow leakage at the bottom seams of one of the tanks; adequacy of earthen dikes surrounding the tanks; odor complaints; and leaks from tank side valves.

  18. Integrated mild gasification processing at the Homer City Electric Power Generating Station site. Final report, July 1989--June 1993

    SciTech Connect

    Battista, J.J.; Zawadzki, E.A.

    1993-07-01

    A new process for the production of commercial grade coke, char, and carbon products has been evaluated by Penelec/NYSEG. The process, developed by Coal Technology Corporation, CTC, utilizes a unique screw reactor to produce a devolatilized char from a wide variety of coals for the production of commercial grade coke for use in blast furnaces, foundries, and other processes requiring high quality coke. This process is called the CTC Mild Gasification Process (MGP). The process economics are significantly enhanced by integrating the new technology into an existing power generating complex. Cost savings are realized by the coke producer, the coke user, and the electric utility company. Site specific economic studies involving the Homer City Generating Station site in Western Pennsylvania, confirmed that an integrated MGP at the Homer City site, using coal fines produced at the Homer City Coal Preparation Plant, would reduce capital and operating costs significantly and would enable the HC Owners to eliminate thermal dryers, obtain low cost fuel in the form of combustible gases and liquids, and obtain lower cost replacement coal on the spot market. A previous report, identified as the Interim Report on the Project, details the technical and economic studies.

  19. Superfund Record of Decision (EPA Region 6): South Cavalcade Street Site, Houston, Texas (first remedial action) September 1988. Final report

    SciTech Connect

    Not Available

    1988-09-26

    The 66-acre South Cavalcade site is located in northeast Houston, Texas. The surrounding areas are a mixture of residential, commercial, and industrial properties. Stormwater runoff flows to two stormwater drainage ditches, which flow into Hunting Bayou, a limited aquatic habitat as classified by Texas Water Quality Standards. The site was used as a wood-preserving and coal-tar distillation facility from 1910 to 1962. The wood preserving facility consisted of an operations area, a drip track, and treated and untreated-wood storage areas. The operations area included wood-treating cylinders, chemical storage tanks, and a waste-water lagoon. Creosote and metallic salts were used in the operation. PAHs, VOCs, metals and components of creosote were detected in the soil, sediments, and ground water. The primary contaminants of concern affecting the ground water, soils, and sediments are VOCs including benzene, toluene, and xylenes, other organics including PAHs, and metal including arsenic, chromium, and lead. The selected remedial action for the site is outlined.

  20. Technical procedures for water resources, Deaf Smith County site, Texas: Volume 2: Environmental Field Program: Final draft

    SciTech Connect

    Not Available

    1987-08-01

    This volume contains the following Technical Procedures pursuant to the Water Resources Site Study Plan operation of a Playa Lake conductivity monitoring station and processing of data from a Playa Lake conductivity monitoring station. This procedure defines steps and methods for the installation, operation, and maintenance of the Playa Lake conductivity monitoring stations. Conductivity measurements will be taken at six playa lakes in the site study area to record changes in total dissolved solids as a function of stage. Playa lake conductivity and stage (volume) measurements will be used, in conjunction with other water quality data collected at the Playa Lake and precipitation stations, to determine the mass of dissolved solids entering and leaving the playas. This baseline information on the pollutant mass balance of the playas will be used to assess potential changes in playa lake water quality and the magnitude of those changes due to site development. The pollutant mass balances will also be used on determining the source of pollutants. 2 refs., 5 figs.