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2008

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Articles 2941 - 2970 of 4190

Full-Text Articles in Engineering

Small Angle Neutron Scattering Study Of Conformation Of Oligo(Ethylene Glycol)-Grafted Polystyrene In Dilute Solutions: Effect Of The Backbone Length, Gang Cheng, Yuri B. Melnichenko, George D. Wignall, Fengjun Hua, Kunlun Hong, Jimmy W. Mays Jan 2008

Small Angle Neutron Scattering Study Of Conformation Of Oligo(Ethylene Glycol)-Grafted Polystyrene In Dilute Solutions: Effect Of The Backbone Length, Gang Cheng, Yuri B. Melnichenko, George D. Wignall, Fengjun Hua, Kunlun Hong, Jimmy W. Mays

United States Department of Energy: Publications

The conformation and clusterization of comblike polymers of polystyrene densely grafted with oligo(ethylene glycol) (OEG) side chains in 1.0 wt % solutions of D2O, toluene-d8, and methanol-d4 was investigated as a function of the degree of polymerization (DP) of the backbone by small angle neutron scattering (SANS). Each side chain had four EG repeat units, and the DP of the polystyrene backbone varied from 8 to 85. The global conformation of the polymers in toluene and methanol was shown to assume ellipsoidal, rigid cylindrical, or wormlike morphologies with increasing DP of the polystyrene …

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A New Fluorinated Polymer Having Two Connected Rings In The Main Chain: Synthesis And Characterization Of Fluorinated Poly(1,3-Cyclohexadiene), Tianzi Huang, Jamie M. Messman, Jimmy W. Mays Jan 2008

A New Fluorinated Polymer Having Two Connected Rings In The Main Chain: Synthesis And Characterization Of Fluorinated Poly(1,3-Cyclohexadiene), Tianzi Huang, Jamie M. Messman, Jimmy W. Mays

United States Department of Energy: Publications

The high electronegativity and small size of the fluorine atom and the high stability of C-F bonds impart interesting properties and applications to fluorine containing polymers. The unique properties of fluoropolymers include high thermal stability, improved chemical resistance, low surface energies, low coefficients of friction, and low dielectric constants. Applications of fluorinated polymers include use as noncorrosive materials, polymer processing aids, chemically resistant and antifouling coatings, as well as interlayer dielectrics. Fluorine-containing polymers can be directly synthesized via polymerization of fluorine-containing monomers or by post-polymerization modification. The latter method can be used to attach fluorinated species, such as perfluoroalkyl groups, …

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Impact Of Solvent Quality On The Density Profiles Of Looped Triblock Copolymer Brushes By Neutron Reflectivity Measurements, Zhenyu Huang, Jose Alonzo, Ming Liu, Haining Ji, Fang Yin, Grant D. Smith, Jimmy W. Mays, S. Michael Kilbey Ii, Mark D. Dadmun Jan 2008

Impact Of Solvent Quality On The Density Profiles Of Looped Triblock Copolymer Brushes By Neutron Reflectivity Measurements, Zhenyu Huang, Jose Alonzo, Ming Liu, Haining Ji, Fang Yin, Grant D. Smith, Jimmy W. Mays, S. Michael Kilbey Ii, Mark D. Dadmun

United States Department of Energy: Publications

Preferential adsorption of poly(2-vinylpyridine)-deuterated polystyrene-poly(2-vinylpyridine) (PVP-dPS-PVP) triblock copolymers from toluene onto silicon leads to the formation of dPS loops tethered by the PVP end blocks. Using neutron reflectometry, we have determined the segment density profiles of these looped polymer brushes in toluene, a good solvent for the dPS block, and in cyclohexane at 20 °C (poor solvent), 32 °C, (near-Θ solvent), and 50 °C (marginal solvent). While the swelling behavior qualitatively agrees with that observed for singly grafted brushes, there are interesting differences in the local structural details: In a good solvent, the segment density profiles are composed of an …

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Hierarchical Assemblies Of Block-Copolymer-Based Supramolecules In Thin Films, Shih-Huang Tung, Nisha C. Kalarickal, Jimmy W. Mays, Ting Xu Jan 2008

Hierarchical Assemblies Of Block-Copolymer-Based Supramolecules In Thin Films, Shih-Huang Tung, Nisha C. Kalarickal, Jimmy W. Mays, Ting Xu

United States Department of Energy: Publications

The hierarchical assemblies of supramolecules, which consisted of polystyrene-b-poly(4- vinylpyridine) (PS-b-P4VP) with 3-pentadecylphenol (PDP) hydrogen-bonded to the 4VP, were investigated in thin films after solvent annealing in a chloroform atmosphere. The synergistic coassembly of PS-b-P4VP and PDP was utilized to generate oriented hierarchical structures in thin films. Hierarchical assemblies, including lamellae-within-lamellae and cylinders-within-lamellae, were simultaneously ordered and oriented from a few to several tens of nanometers over macroscopic length scales. The macroscopic orientation of supramolecular assembly depends on the P4VP(PDP) fraction and can be tailored by varying the PDP to P4VP ratio without interfering …

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Association And Structure Of Thermosensitive Comblike Block Copolymers In Aqueous Solutions, Gang Cheng, Fengjun Hua, Yuri B. Melnichenko, Kunlun Hong, Jimmy W. Mays, Boualem Hammouda, George D. Wignall Jan 2008

Association And Structure Of Thermosensitive Comblike Block Copolymers In Aqueous Solutions, Gang Cheng, Fengjun Hua, Yuri B. Melnichenko, Kunlun Hong, Jimmy W. Mays, Boualem Hammouda, George D. Wignall

United States Department of Energy: Publications

The structures and association properties of thermosensitive block copolymers of poly(methoxyoligo( ethylene glycol) norbornenyl esters) in D2O were investigated by small angle neutron scattering (SANS). Each block is a comblike polymer with a polynorbornene (PNB) backbone and oligo ethylene glycol (OEG) side chains (one side chain per NB repeat unit). The chemical formula of the block copolymer is (OEG3NB) 79- (OEG6.6NB) 67, where subscripts represent the degree of polymerization (DP) of OEG and NB in each block. The polymer concentration was fixed at 2.0 wt % and the structural changes were investigated …

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Biogeochemical Processes In Ethanol Stimulated Uranium-Contaminated Subsurface Sediments, Santosh R. Mohanty, Bharati Kollah, David B. Hedrick, Aaron D. Peacock, Ravi K. Kukkadapu, E. E. Roden Jan 2008

Biogeochemical Processes In Ethanol Stimulated Uranium-Contaminated Subsurface Sediments, Santosh R. Mohanty, Bharati Kollah, David B. Hedrick, Aaron D. Peacock, Ravi K. Kukkadapu, E. E. Roden

United States Department of Energy: Publications

A laboratory incubation experiment was conducted with uranium contaminated subsurface sediment to assess the geochemical and microbial community response to ethanol amendment. A classical sequence of terminal electron-accepting processes (TEAPs) was observed in ethanol-amended slurries, with NO3- reduction, Fe(III) reduction, SO42- reduction, and CH4 production proceeding in sequence until all of the added 13Cethanol (9 mM) was consumed. Approximately 60% of the U(VI) content of the sediment was reduced during the period of Fe(III) reduction. No additional U(VI) reduction took place during the sulfate-reducing and methanogenic phases of the experiment. Only gradual reduction of NO …

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Reduction Of Tc(Vii) By Fe(Ii) Sorbed On Al (Hydr)Oxides, T. Peretyazhko, J.M. Zachara, S.M. Heald, Ravi K. Kukkadapu, C. Liu, A.E. Plymale, C.T. Resch Jan 2008

Reduction Of Tc(Vii) By Fe(Ii) Sorbed On Al (Hydr)Oxides, T. Peretyazhko, J.M. Zachara, S.M. Heald, Ravi K. Kukkadapu, C. Liu, A.E. Plymale, C.T. Resch

United States Department of Energy: Publications

Under oxic conditions, Tc exists as the soluble, weakly sorbing pertechnetate [TcO4-] anion. The reduced form of technetium, Tc(IV), is stable in anoxic environments and is sparingly soluble as TcO2 ·nH2O(s). Here we investigate the heterogeneous reduction of Tc(VII) by Fe(II) adsorbed on Al (hydr)oxides [diaspore (α-AlOOH) and corundum (α-Al2O3)]. Experiments were performed to study the kinetics of Tc(VII) reduction, examine changes in Fe surface speciation during Tc(VII) reduction (Mössbauer spectroscopy), and identify the nature of Tc(IV)-containing reaction products (X-ray absorption spectroscopy). We found that Tc(VII) was completely …

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Long-Term Dynamics Of Uranium Reduction/Reoxidation Under Low Sulfate Conditions, John Komlos, Aaron Peacock, Ravi K. Kukkadapu, Peter R. Jaffe Jan 2008

Long-Term Dynamics Of Uranium Reduction/Reoxidation Under Low Sulfate Conditions, John Komlos, Aaron Peacock, Ravi K. Kukkadapu, Peter R. Jaffe

United States Department of Energy: Publications

The biological reduction and precipitation of uranium in groundwater has the potential to prevent uranium migration from contaminated sites. Although previous research has shown that uranium bioremediation is maximized during iron reduction, little is known on how long-term iron/uranium reducing conditions can be maintained. Questions also remain about the stability of uranium and other reduced species after a long-term biostimulation scheme is discontinued and oxidants (i.e., oxygen) re-enter the bioreduced zone. To gain further insights into these processes, four columns, packed with sediment containing iron as Fe-oxides (mainly Al-goethite) and silicate Fe (Fe-containing clays), were operated in the laboratory under …

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Kinetics Of Reduction Of Fe(Iii) Complexes By Outer Membrane Cytochromes Mtrc And Omca Of Shewanella Oneidensis Mr-1, Zheming Wang, Chongxuan Liu, Xuelin Wang, Matthew J. Marshall, John M. Zachara, Kevin M. Rosso, Michel Dupuis, James K. Fredrickson, Steve Heald, Liang Shi Jan 2008

Kinetics Of Reduction Of Fe(Iii) Complexes By Outer Membrane Cytochromes Mtrc And Omca Of Shewanella Oneidensis Mr-1, Zheming Wang, Chongxuan Liu, Xuelin Wang, Matthew J. Marshall, John M. Zachara, Kevin M. Rosso, Michel Dupuis, James K. Fredrickson, Steve Heald, Liang Shi

United States Department of Energy: Publications

Because of their cell surface locations, the outer membrane c-type cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 have been suggested to be the terminal reductases for a range of redox-reactive metals that form poorly soluble solids or that do not readily cross the outer membrane. In this work, we determined the kinetics of reduction of a series of Fe(III) complexes with citrate, nitrilotriacetic acid (NTA), and EDTA by MtrC and OmcA using a stopped-flow technique in combination with theoretical computation methods. Stopped-flow kinetic data showed that the reaction proceeded in two stages, a fast stage that was completed …

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Hydrogenase- And Outer Membrane C-Type Cytochrome-Facilitated Reduction Of Technetium(Vii) By Shewanella Oneidensis Mr-1, Matthew J. Marshall, Andrew Plymale, David W. Kennedy, Liang Shi, Zheming Wang, Samantha B. Reed, Alice Dohnalkova, Cody Simonson, Chongxuan Liu, Daad A. Saffarini, Margaret F. Romine, John M. Zachara, Alexander S. Beliaev, James K. Fredrickson Jan 2008

Hydrogenase- And Outer Membrane C-Type Cytochrome-Facilitated Reduction Of Technetium(Vii) By Shewanella Oneidensis Mr-1, Matthew J. Marshall, Andrew Plymale, David W. Kennedy, Liang Shi, Zheming Wang, Samantha B. Reed, Alice Dohnalkova, Cody Simonson, Chongxuan Liu, Daad A. Saffarini, Margaret F. Romine, John M. Zachara, Alexander S. Beliaev, James K. Fredrickson

United States Department of Energy: Publications

Pertechnetate, 99Tc(VII)O4–, is a highly mobile radionuclide contaminant at US Department of Energy sites that can be enzymatically reduced by a range of anaerobic and facultatively anaerobic microorganisms, including Shewanella oneidensis MR-1, to poorly soluble Tc(IV)O2(s). In other microorganisms, Tc(VII)O4– reduction is generally considered to be catalysed by hydrogenase. Here, we provide evidence that although the NiFe hydrogenase of MR-1 was involved in the H2-driven reduction of Tc(VII)O4– [presumably through a direct coupling of H2 oxidation and Tc(VII) reduction], the deletion of both hydrogenase genes did not completely eliminate …

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Electron Transfer At The Microbe–Mineral Interface: A Grand Challenge In Biogeochemistry, James K. Fredrickson, John M. Zachara Jan 2008

Electron Transfer At The Microbe–Mineral Interface: A Grand Challenge In Biogeochemistry, James K. Fredrickson, John M. Zachara

United States Department of Energy: Publications

The interplay between microorganisms and minerals is a complex and dynamic process that has sculpted the geosphere for nearly the entire history of the Earth. The work of Dr. Terry Beveridge and colleagues provided some of the first insights into metal–microbe and mineral–microbe interactions and established a foundation for subsequent detailed investigations of interactions between microorganisms and minerals. Beveridge also envisioned that interdisciplinary approaches and teams would be required to explain how individual microbial cells interact with their immediate environment at nano- or microscopic scales and that through such approaches and using emerging technologies that the details of such interactions …

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The Minimum Information About A Genome Sequence (Migs) Specification, Dawn Field, George Garrity, Tanya Gray, Norman Morrison, Jeremy Selengut, Peter Sterk, Tatiana Tatusova, Nicholas Thomson, Michael J. Allen, Samuel V. Angiuoli, Michael Ashburner, Nelson Axelrod, Sandra Baldauf, Stuart Ballard, Jeffrey Boore, Guy Cochrane, James Cole, Peter Dawyndt, Paul De Vos, Claude Depamphilis, Robert Edwards, Nadeem Faruque, Robert Feldman, Jack Gilbert, Paul Gilna, Frank Oliver Glöckner, Philip Goldstein, Robert Guralnick, Dan Haft, David Hancock, Henning Hermjakob, Christiane Hertz-Fowler, Phil Hugenholtz, Ian Joint, Leonid Kagan, Matthew Kane, Jessie Kennedy, George Kowalchuk, Renzo Kottmann, Eugene Kolker, Saul Kravitz, Nikos Kyrpides, Jim Leebens-Mack, Suzanna E. Lewis, Kelvin Li, Allyson L. Lister, Phillip Lord, Natalia Maltsev, Victor Markowitz, Jennifer Martiny, Barbara Methe, Ilene Mizrachi, Richard Moxon, Karen Nelson, Julian Parkhill, Lita Proctor, Owen White, Susanna-Assunta Sansone, Andrew Spiers, Robert Stevens, Paul Swift, Chris Taylor, Yoshio Tateno, Adrian Tett, Sarah Turner, David Ussery, Bob Vaughan, Naomi Ward, Trish Whetzel, Ingio San Gil, Gareth Wilson, Anil Wipat Jan 2008

The Minimum Information About A Genome Sequence (Migs) Specification, Dawn Field, George Garrity, Tanya Gray, Norman Morrison, Jeremy Selengut, Peter Sterk, Tatiana Tatusova, Nicholas Thomson, Michael J. Allen, Samuel V. Angiuoli, Michael Ashburner, Nelson Axelrod, Sandra Baldauf, Stuart Ballard, Jeffrey Boore, Guy Cochrane, James Cole, Peter Dawyndt, Paul De Vos, Claude Depamphilis, Robert Edwards, Nadeem Faruque, Robert Feldman, Jack Gilbert, Paul Gilna, Frank Oliver Glöckner, Philip Goldstein, Robert Guralnick, Dan Haft, David Hancock, Henning Hermjakob, Christiane Hertz-Fowler, Phil Hugenholtz, Ian Joint, Leonid Kagan, Matthew Kane, Jessie Kennedy, George Kowalchuk, Renzo Kottmann, Eugene Kolker, Saul Kravitz, Nikos Kyrpides, Jim Leebens-Mack, Suzanna E. Lewis, Kelvin Li, Allyson L. Lister, Phillip Lord, Natalia Maltsev, Victor Markowitz, Jennifer Martiny, Barbara Methe, Ilene Mizrachi, Richard Moxon, Karen Nelson, Julian Parkhill, Lita Proctor, Owen White, Susanna-Assunta Sansone, Andrew Spiers, Robert Stevens, Paul Swift, Chris Taylor, Yoshio Tateno, Adrian Tett, Sarah Turner, David Ussery, Bob Vaughan, Naomi Ward, Trish Whetzel, Ingio San Gil, Gareth Wilson, Anil Wipat

United States Department of Energy: Publications

With the quantity of genomic data increasing at an exponential rate, it is imperative that these data be captured electronically, in a standard format. Standardization activities must proceed within the auspices of open-access and international working bodies. To tackle the issues surrounding the development of better descriptions of genomic investigations, we have formed the Genomic Standards Consortium (GSC). Here, we introduce the minimum information about a genome sequence (MIGS) specification with the intent of promoting participation in its development and discussing the resources that will be required to develop improved mechanisms of metadata capture and exchange. As part of its …

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Genomics: Gtl 2008 Strategic Plan, Sharlene Weatherwax Jan 2008

Genomics: Gtl 2008 Strategic Plan, Sharlene Weatherwax

United States Department of Energy: Publications

Table of Contents:
Mission-Inspired Science
GTL Concept and History
National Academy of Sciences Evaluation of GTL Program
GTL’s Fundamental Research Approach to Its Mission
Hallmarks of the GTL Research Approach
Multiscale Explorations
Office of Biological and Environmental Research User Facilities
Metamethods: Metagenomics and Metaproteomics
Robust Computational Framework for GTL Research
GTL Information and Data Sharing Policy
Elaboration of GTL Science for DOE Missions
Systems Biology for Energy Solutions
Systems Biology for Understanding the Carbon Cycle
Planet-Transforming Microbes
Systems Biology for Understanding Contaminant Transport in the Environment
Microbe-Mineral Interface in Contaminated Environments
DOE Office of Science
DOE Office of Biological and …

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Pursuing Energy Efficiency As A Hedge Against Carbon Regulatory Risks: Current Resource Planning Practices In The West, Ryan Wiser, Amol Phadke, Charles Goldman Jan 2008

Pursuing Energy Efficiency As A Hedge Against Carbon Regulatory Risks: Current Resource Planning Practices In The West, Ryan Wiser, Amol Phadke, Charles Goldman

United States Department of Energy: Publications

Uncertainty surrounding the nature and timing of future carbon regulations poses a fundamental and far-reaching financial risk for electric utilities and their ratepayers. Long-term resource planning provides a potential framework within which utilities can assess carbon regulatory risk and evaluate options for mitigating exposure to this risk through investments in energy efficiency and other low-carbon resources. In this paper, we examine current resource planning practices related to managing carbon regulatory risk, based on a comparative analysis of the most-recent long-term resource plans filed by fifteen major utilities in the Western U.S. First, we compare the assumptions and methods used by …

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Tribal Renewable Energy – Final Report, A. David Lester Jan 2008

Tribal Renewable Energy – Final Report, A. David Lester

United States Department of Energy: Publications

DOE/CERT Cooperative Agreement has demonstrated that Indian Tribes are ready to undertake the positive steps in developing their internal governmental capacities in program planning and project development as well as the enterprise management capability to undertake the development of their substantial natural base of renewable energy resources and to learn the basic technologies in wind, solar, bio-mass and alternative energy production. The project also demonstrated that virtually every Indian Tribe and community in the United States would benefit socially, economically and in public health values thru a sustained federally coordinated Tribal energy efficiency initiative; and, that a small amount of …

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Preservation And Analytical Procedures For The Analysis Of Chloro-S-Triazines And Their Chlorodegradate Products In Drinking Waters Using Direct Injection Liquid Chromatography Tandem Mass Spectrometry, Glynda A. Smith, Barry V. Pepich, David J. Munch Jan 2008

Preservation And Analytical Procedures For The Analysis Of Chloro-S-Triazines And Their Chlorodegradate Products In Drinking Waters Using Direct Injection Liquid Chromatography Tandem Mass Spectrometry, Glynda A. Smith, Barry V. Pepich, David J. Munch

United States Environmental Protection Agency: Publications

A direct injection, liquid chromatography tandemmass spectrometry (LC–MS/MS)method has been developed for the analysis of the chloro-s-triazine herbicides and their degradates in finished drinking water. The target compounds in the method were selected based on their inclusion in a common mechanism group (CMG) because of their ability to induce a similar toxic effect through a common mechanism of toxicity. The target list includes the chloro-s-triazines (atrazine, simazine, cyanazine, and propazine) and their dealkylated degradates (desethylatrazine, desisopropylatrazine, and diaminochlorotriazine). Potential matrix effects are minimized by the use of individual isotopically enriched internal standards. Analyte stability in finished …

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Past And Projected Rural Land Conversion In The Us At State, Regional, And National Levels, Eric M. White, Anita T. Morzilla, Ralph J. Alig Jan 2008

Past And Projected Rural Land Conversion In The Us At State, Regional, And National Levels, Eric M. White, Anita T. Morzilla, Ralph J. Alig

United States Environmental Protection Agency: Publications

The developed land area of the US increased by 14.2 million hectares between 1982 and 2003. Along with a projected US population increase to more than 360 million individuals by 2030 is an expected continuation of expanding rural land development. Related to population growth, rural land development and the associated loss of rural open space are expected to have a number of social, economic, and ecological implications. To gain greater insight into land development patterns, we used US Census Bureau and National Resources Inventory data to quantify per-housing-unit rates of land development during recent decades and to model future land …

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Linkage Of The Us National Health Interview Survey To Air Monitoring Data: An Evaluation Of Different Strategies, Jennifer D. Parker, Tracey Woodruff, Lara J. Akinbami, Natalyia Kravets Jan 2008

Linkage Of The Us National Health Interview Survey To Air Monitoring Data: An Evaluation Of Different Strategies, Jennifer D. Parker, Tracey Woodruff, Lara J. Akinbami, Natalyia Kravets

United States Environmental Protection Agency: Publications

The goal of this study is to describe linkages between the National Health Interview Survey (NHIS) and Environmental Protection Agency (EPA) air monitoring data, specifically how the linkage method affects characteristics and exposure estimates of study samples and estimated associations between exposure and health. In the USA, nationally representative health data are collected in the NHIS and annual air quality data are collected by the EPA. The linkage of these data for research is not straightforward and the choices made may introduce bias into results. The 2000–2003 NHIS and air quality data for six air pollutants were linked by residential …

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Cyanobacterial Harmful Algal Blooms: Chapter 31: Ecosystem Effects Workgroup Report, John Fournie, Elizabeth Hilborn, Geoffrey Codd, Michael Coveney, Juli Dyble, Karl Havens, Bas Ibelings, Jan Landsberg, Wayne Litaker Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 31: Ecosystem Effects Workgroup Report, John Fournie, Elizabeth Hilborn, Geoffrey Codd, Michael Coveney, Juli Dyble, Karl Havens, Bas Ibelings, Jan Landsberg, Wayne Litaker

United States Environmental Protection Agency: Publications

Harmful cyanobacterial blooms represent one of the most serious ecological stressors in lakes, rivers, estuaries and marine environments. When there are persistent or frequent blooms with high biomass of cyanobacterial cells, colonies or filaments in the water, a wide range of impacts on the ecosystem may occur. These are well established in the scientific literature and are summarized in Paerl et al. (2001). Blooms may shade the water and thereby inhibit growth of other primary producers including phytoplankton, benthic algae and vascular plants and may elevate pH, particularly in poorly buffered waters. High population densities of large cyanobacteria interfere with …

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Cyanobacterial Harmful Algal Blooms: Chapter 1: An Overview Of The Interagency, International Symposium On Cyanobacterial Harmful Algal Blooms (Isoc-Hab): Advancing The Scientific Understanding Of Freshwater Harmful Algal Blooms, H. Kenneth Hudnell, Quay Dortch, Harold Zenick Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 1: An Overview Of The Interagency, International Symposium On Cyanobacterial Harmful Algal Blooms (Isoc-Hab): Advancing The Scientific Understanding Of Freshwater Harmful Algal Blooms, H. Kenneth Hudnell, Quay Dortch, Harold Zenick

United States Environmental Protection Agency: Publications

There is growing evidence that the spatial and temporal incidence of harmful algal blooms is increasing, posing potential risks to human health and ecosystem sustainability. Currently there are no US Federal guidelines, Water Quality Criteria and Standards, or regulations concerning the management of harmful algal blooms. Algal blooms in freshwater are predominantly cyanobacteria, some of which produce highly potent cyanotoxins. The US Congress mandated a Scientific Assessment of Freshwater Harmful Algal Blooms in the 2004 reauthorization of the Harmful Algal Blooms and Hypoxia Research and Control Act. To further the scientific understanding of freshwater harmful algal blooms, the US Environmental …

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Cyanobacterial Harmful Algal Blooms: Chapter 35: Risk Assessment Workgroup Report, Joyce Donohue, Jennifer Orme–Zavaleta, Michael Burch, Daniel Dietrich, Belinda Hawkins, Tony Lloyd, Wayne Munns, Jeffery Steevens, Dennis Steffensen, Dave Stone, Peter Tango Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 35: Risk Assessment Workgroup Report, Joyce Donohue, Jennifer Orme–Zavaleta, Michael Burch, Daniel Dietrich, Belinda Hawkins, Tony Lloyd, Wayne Munns, Jeffery Steevens, Dennis Steffensen, Dave Stone, Peter Tango

United States Environmental Protection Agency: Publications

Risk assessment is a four–stage process used in evaluating the impact of contaminants on the well being of individuals, populations and/or the physical environment. As defined by the National Academy of Sciences (1983), the four components are as follows: hazard identification, dose– response assessment, exposure assessment and risk characterization.
The goal of a risk assessment is to utilize existing information coupled with site specific data to quantitatively characterize the potential risk of a stressor to an identified receptor(s). Quantitative, risk–based estimates of dose–response relationships integrated with exposure scenarios and information on environmental conditions often become the basis for regulatory measures …

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Cyanobacterial Harmful Algal Blooms: Chapter 26: Human Health Effects Workgroup Report, Sandra Azevedo, Neil Chernoff, Ian Falconer, Michael Gage, Elizabeth Hilborn, Michelle Hooth, Karl Jensen, Robert Macphail, Ellen Rogers, Glen Shaw, Ian Stewart Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 26: Human Health Effects Workgroup Report, Sandra Azevedo, Neil Chernoff, Ian Falconer, Michael Gage, Elizabeth Hilborn, Michelle Hooth, Karl Jensen, Robert Macphail, Ellen Rogers, Glen Shaw, Ian Stewart

United States Environmental Protection Agency: Publications

Two types of approaches may be used to evaluate the toxicity of environmental agents:

• Observational population studies may be used to investigate humans or animals in contact with the agent of interest, either prospectively or retrospectively.
• Experimental studies may be performed under controlled conditions on animals, living tissues or cells. These results may be extrapolated to human and animal populations.

Observational epidemiological studies of human and animal populations have the advantage of investigating the effects of environmentally relevant exposures to naturally–occurring mixtures of toxins. Health effects may be identified in the target species of concern. These studies are …

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Cyanobacterial Harmful Algal Blooms: Chapter 38: Integrating Human And Ecological Risk Assessment: Application To The Cyanobacterial Harmful Algal Bloom Problem, Jennifer Orme-Zavaleta, Wayne Munns, Jr. Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 38: Integrating Human And Ecological Risk Assessment: Application To The Cyanobacterial Harmful Algal Bloom Problem, Jennifer Orme-Zavaleta, Wayne Munns, Jr.

United States Environmental Protection Agency: Publications

Environmental and public health policy continues to evolve in response to new and complex social, economic and environmental drivers. Globalization and centralization of commerce, evolving patterns of land use (e.g., urbanization, deforestation), and technological advances in such areas as manufacturing and development of genetically modified foods have created new and complex classes of stressors and risks (e.g., climate change, emergent and opportunist disease, sprawl, genomic change). In recognition of these changes, environmental risk assessment and its use are changing from stressor-endpoint specific assessments used in command and control types of decisions to an integrated approach for application in communitybased decisions. …

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Cyanobacterial Harmful Algal Blooms: Chapter 15: Cyanotoxins Workgroup Report, Rex Pegram, Andrew Humpage, Brett Neilan, Maria Runnegar, Tonya Nichols, Robert Thacker, Stephan Pflugmacher, Stacey Etheridge, Adam Love Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 15: Cyanotoxins Workgroup Report, Rex Pegram, Andrew Humpage, Brett Neilan, Maria Runnegar, Tonya Nichols, Robert Thacker, Stephan Pflugmacher, Stacey Etheridge, Adam Love

United States Environmental Protection Agency: Publications

The Cyanotoxins Workgroup was charged with the identification and prioritization of research needs associated with: the identification of cyanotoxins; toxicokinetics and toxicodynamics of cyanotoxins; human susceptibility to the toxins; cyanobacterial genetics/omics and factors for inclusion in predictive models of toxin production; and risk reduction from an intentional or accidental release of cyanotoxins. Papers presented for the Cyanotoxins Session of the symposium on toxin types, toxicokinetics, and toxicodyamics (See Humpage this volume), cyanobacterial genetics of toxin production (See Neilan this volume), and parameters related to human risks from cyanobacterial exposure (See Love this volume) set the stage for Cyanotoxins Workgroup discussions. …

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Cyanobacterial Harmful Algal Blooms: Chapter 2: A Synopsis Of Research Needs Identified At The Interagency, International Symposium On Cyanobacterial Harmful Algal Blooms (Isoc-Hab), H. Kenneth Hudnell, Quay Dortch Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 2: A Synopsis Of Research Needs Identified At The Interagency, International Symposium On Cyanobacterial Harmful Algal Blooms (Isoc-Hab), H. Kenneth Hudnell, Quay Dortch

United States Environmental Protection Agency: Publications

Evidence indicates that the incidence of cyanobacterial harmful algal blooms (CHABs) is increasing in spatial extent and temporal frequency worldwide. Cyanobacterial blooms produce highly potent toxins and huge, noxious biomasses in surface waters used for recreation, commerce, and as drinking water sources. The Interagency, International Symposium on Cyanobacterial Harmful Algal Blooms (ISOC-HAB) characterized the state of the science and identified research needed to address the risks posed by CHABs to human health and ecosystem sustainability. This chapter provides a synopsis of CHAB research needs that were identified by workgroups that addressed charges in major topic areas. The research and infrastructure …

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Cyanobacterial Harmful Algal Blooms: Chapter 3: Occurrence Of Cyanobacterial Harmful Algal Blooms Workgroup Report, Anthony Fristachi, James Sinclair, Sherwood Hall, Julie Hambrook Berkman, Greg Boyer, Joann Burkholder, John Burns, Wayne Carmichael, Al Dufour, William Frazier, Steve Morton, Eric O’Brien, Steven Walker Jan 2008

Cyanobacterial Harmful Algal Blooms: Chapter 3: Occurrence Of Cyanobacterial Harmful Algal Blooms Workgroup Report, Anthony Fristachi, James Sinclair, Sherwood Hall, Julie Hambrook Berkman, Greg Boyer, Joann Burkholder, John Burns, Wayne Carmichael, Al Dufour, William Frazier, Steve Morton, Eric O’Brien, Steven Walker

United States Environmental Protection Agency: Publications

Freshwater cyanobacteria periodically accumulate, or bloom, in water bodies across the United States (US). These blooms, also known as cyanobacterial harmful algal blooms (CHAB), can lead to a reduction in the number of individuals who engage in recreational activities in lakes and reservoirs, degrade aquatic habitats and potentially impact human health. In 1998, Congress passed the 1998 Harmful Algal Bloom and Hypoxia Research and Control Act (HABHRCA) to address CHABs that impacted living marine resources, fish and shellfish harvests and recreational and service industries along US coastal waters. In 2004, as part of its reauthorization, HABHRCA requires federal agencies to …

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Nitrogen In The Environment: Chapter 22. New Policy Directions, A.P. Manale Jan 2008

Nitrogen In The Environment: Chapter 22. New Policy Directions, A.P. Manale

United States Environmental Protection Agency: Publications

Advances in linking the science of ecology with economics and the development of agri-environmental modeling systems coupled with new information technology suggest new public policy approaches that reward agricultural producers for providing ecological services. An incentive-based ecosystem approach that identifies and quantifies an array of environmental services that can be provided by agricultural land, and then facilitates the development of markets in these services can protect environmental quality while improving farm income. Sustainability can be achieved whereby economic needs of society are integrated into environmental protection. Before presenting new agricultural policy approaches for improving environmental quality and, in particular, managing …

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Bridging The Gaps Between Design And Use: Developing Tools To Support Environmental Management And Policy, B. S. Mcintosh, C. Giupponi, A. A. Voinov, C. Smith, K. B. Matthews, M. Monticino, M. J. Kolkman, N. Crossman, M. Van Ittersum, D. Haase, A. Haase, J. Mysiak, J. Groot, S. Sieber, P. Verweij, N. Quinn, P. Waeger, N. Gaber, D. Hepting, H. Scholten, A. Sulis, H. Van Delden, E. Gaddis, H. Assaf Jan 2008

Bridging The Gaps Between Design And Use: Developing Tools To Support Environmental Management And Policy, B. S. Mcintosh, C. Giupponi, A. A. Voinov, C. Smith, K. B. Matthews, M. Monticino, M. J. Kolkman, N. Crossman, M. Van Ittersum, D. Haase, A. Haase, J. Mysiak, J. Groot, S. Sieber, P. Verweij, N. Quinn, P. Waeger, N. Gaber, D. Hepting, H. Scholten, A. Sulis, H. Van Delden, E. Gaddis, H. Assaf

United States Environmental Protection Agency: Publications

Sound decisions in environmental policy and management usually require the examination of alternative solutions, and may require the consideration of alternative problem fornlulations prior to option assessment. Constructing and considering the consequences of alternative problems (variables and relations) and policy options (norms and standards) is fundamental for processes of policy fornlulation (Vickers, 1965).

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Complexity And Uncertainty: Rethinking The Modelling Activity, M. Brugnach, C. Pahl-Wostl, K. E. Lindenschmidt, J. A.E.B. Janssen, T. Filatova, A. Mouton, G. Holtz, P. Van Der Keur, N. N. Gaber Jan 2008

Complexity And Uncertainty: Rethinking The Modelling Activity, M. Brugnach, C. Pahl-Wostl, K. E. Lindenschmidt, J. A.E.B. Janssen, T. Filatova, A. Mouton, G. Holtz, P. Van Der Keur, N. N. Gaber

United States Environmental Protection Agency: Publications

Complexity and uncertainty have become critical considerations for environmental modelling applications, opening ne\v avenues for the use and development of models. Increasingly l110dels are being recognized as essential tools to learn, coml11unicate, explore and resolve the particulars of complex environmental problems (Sterman, 2002; Van den Belt, 2(04). However, this shift in the way in which models have been used has not always been accompanied by a concomitant shift in the way in which models have been conceived and implemented. Too often, models were conceived and built as predictive devices, aimed at capturing single, best, objective explanations. Considerations of uncertainty were …

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2008 Epa’S Report On The Environment: Indicators Presenting Data For Epa Region 7, United States Environmental Protection Agency Jan 2008

2008 Epa’S Report On The Environment: Indicators Presenting Data For Epa Region 7, United States Environmental Protection Agency

United States Environmental Protection Agency: Publications

EPA’s 2008 Report on the Environment (ROE) compiles, in one place, the most reliable indicators currently available to answer 23 questions that EPA believes are of critical importance to its mission to protect human health and the environment.
The indicators are supported by data gathered from federal and state agencies and non-governmental organizations. All ROE indicators were peer-reviewed to meet exacting standards for accuracy, representativeness, and reliability, and the report has undergone extensive internal and interagency review, SAB review, and public comment. The indicators present trends wherever adequate data are available, and establish national baselines where they are not. The …

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