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2009

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Measurement Of Sediment Oxygen Demand (Sod) In Upper New Meadows River And Quahog Bay Estuarine Areas, Maine, Tim Bridges Jan 2009

Measurement Of Sediment Oxygen Demand (Sod) In Upper New Meadows River And Quahog Bay Estuarine Areas, Maine, Tim Bridges

Publications

The Maine Department of Environmental Protection (MDEP), Bureau of Land and Water Quality and EPA’s Regional Office of Environmental Protection requested EPA’s Office of Environmental Measurement and Evaluation assistance in evaluating the sediment oxygen demand (SOD) in the New Meadows Rivers and Quahog Bay estuarine areas of south coastal Maine. The New Meadows River and Quahog Bay estuaries are part of the Casco Bay estuarine system east southeast of Brunswick and west of Bath.

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Life History Parameters Of The Humpback Whale (Megaptera Novaengliae) In The Waters Of The Gulf Of Maine For The 2007 Feeding Season, Meghan Wert Jan 2009

Life History Parameters Of The Humpback Whale (Megaptera Novaengliae) In The Waters Of The Gulf Of Maine For The 2007 Feeding Season, Meghan Wert

Undergraduate Review

The humpback whale (Megaptera novaengliae) is an endangered species of baleen whale that feeds in the waters of the Gulf of Maine during the spring, summer and fall. The worldwide population of humpback whales ranges from 60,000 to 80,000 individuals and the population within the Gulf of Maine is estimated between 9,000 to 11,000. Humpback whales are a large baleen whale that reaches an average length of 40 to 50 feet and a weight of 35 to 40 tons. Although protected worldwide since the International Whaling Commission in 1964, this population has increased slowly and is still considered …

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The Tiger Career Fair Fall 2009, Clemson University Jan 2009

The Tiger Career Fair Fall 2009, Clemson University

Tiger Newspapers

No abstract provided.

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Acorn: Entrepreneurial Narrative And History, William B. Gartner Jan 2009

Acorn: Entrepreneurial Narrative And History, William B. Gartner

Entrepreneurial Studies

In order to learn how the entrepreneurial imagination works, it is important to study the stories that entrepreneurs tell about how they turned their ideas into businesses. In ACORN, the Spiro Institute for Entrepreneurial Leadership presents interviews with entrepreneurs as they tell their stories about the creation of their businesses. Not only do these interviews offer insights into the activities specific to venture creation, but they also demonstrate some of the thought processes involved. This volume focuses on entrepreneurs who have started businesses based around new technologies at Clemson University.

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Cujo Goes To College: On The Use Of Animals By Individuals With Disabilities In Postsecondary Institutions, Dawinder S. Sidhu Jan 2009

Cujo Goes To College: On The Use Of Animals By Individuals With Disabilities In Postsecondary Institutions, Dawinder S. Sidhu

Faculty Scholarship

This Article examines the extent to which animals may be used by individuals with disabilities in a particular setting-postsecondary institutions.

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2009-2010 Unm Catalog, Unm Office Of The Registrar Jan 2009

2009-2010 Unm Catalog, Unm Office Of The Registrar

Course Catalogs

Course catalog for the years 2009-2010.

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2009 Program, Belmont University Jan 2009

2009 Program, Belmont University

Humanities Symposium Programs

No abstract provided.

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Ovine Progressive Pneumonia Provirus Levels Are Unaffected By The Prion 171r Allele In An Idaho Sheep Flock, Robert D. Harrington, Lynn M. Herrmann-Hoesing, Stephen N. White, Katherine I. O'Rourke, Donald P. Knowles Jan 2009

Ovine Progressive Pneumonia Provirus Levels Are Unaffected By The Prion 171r Allele In An Idaho Sheep Flock, Robert D. Harrington, Lynn M. Herrmann-Hoesing, Stephen N. White, Katherine I. O'Rourke, Donald P. Knowles

Zoonotics and Wildlife Disease: Publications

Selective breeding of sheep for arginine (R) at prion gene (PRNP) codon 171 confers resistance to classical scrapie. However, other effects of 171R selection are uncertain. Ovine progressive pneumonia/Maedi-Visna virus (OPPV) may infect up to 66% of a flock thus any affect of 171R selection on OPPV susceptibility or disease progression could have major impact on the sheep industry. Hypotheses that the PRNP 171R allele is 1) associated with the presence of OPPV provirus and 2) associated with higher provirus levels were tested in an Idaho ewe flock. OPPV provirus was found in 226 of 358 …

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Agroforestry: Working Trees For Sequestering Carbon On Agricultural Lands, Michele M. Schoeneberger Jan 2009

Agroforestry: Working Trees For Sequestering Carbon On Agricultural Lands, Michele M. Schoeneberger

Working Trees (USDA-NAC)

No abstract provided.

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Scwds Briefs: Volume 24, Number 4 (January 2009), Gary L. Doster , Editor, Scwds Briefs, Michael J. Yabsley Jan 2009

Scwds Briefs: Volume 24, Number 4 (January 2009), Gary L. Doster , Editor, Scwds Briefs, Michael J. Yabsley

Southeastern Cooperative Wildlife Disease Study: Publications

Table of Contents:

HD in 2007: A Year to Remember

Ecology of AIV in Shorebirds

New USDA Brucellosis Proposal

TWS Seeks Comments on Draft Lead Policy

Unusual Eagle Death

New SCWDS Grad Students

Tennessee Director Retiring

3rd International CWD Symposium

Another SCWDS Student Award

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Surface-Initiated Titanium-Mediated Coordination Polymerization From Catalyst-Functionalized Single And Multiwalled Carbon Nanotubes, Dimitrios Priftis, Nikolaos Petzetakis, Georgios Sakellariou, Marinos Pitsikalis, Durairaj Baskaran, Jimmy W. Mays, Nikos Hadjichristidis Jan 2009

Surface-Initiated Titanium-Mediated Coordination Polymerization From Catalyst-Functionalized Single And Multiwalled Carbon Nanotubes, Dimitrios Priftis, Nikolaos Petzetakis, Georgios Sakellariou, Marinos Pitsikalis, Durairaj Baskaran, Jimmy W. Mays, Nikos Hadjichristidis

United States Department of Energy: Publications

Single (SWNTs) and multiwalled (MWNTs) carbon nanotubes were functionalized with a titanium alkoxide catalyst through a Diels-Alder cycloaddition reaction. The catalyst-functionalized carbon nanotubes (CNTs) were used for the surface initiated titanium-mediated coordination polymerizations of L-lactide (L-LA), ε-caprolactone (ε-CL) and n-hexyl isocyanate (HIC) employing the “grafting from” technique. 1H NMR, IR and Raman spectra showed that the precursor catalyst was successfully synthesized and covalently attached on the CNTs surface. Thermogravimetric analysis (TGA) revealed that the grafted poly(L-lactide) (PLLA) content could be controlled with time. The final polymer-grafted CNTs were readily dissolved in organic solvents as compared to the insoluble pristine …

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Biomineralization Associated With Microbial Reduction Of Fe3+ And Oxidation Of Fe2+ In Solid Minerals, Gengxin Zhang, Hailiang Dong, Hongchen Jiang, Ravi K. Kukkadapu, Jinwook Kim, Dennis Eberl, Zhiqin Xu Jan 2009

Biomineralization Associated With Microbial Reduction Of Fe3+ And Oxidation Of Fe2+ In Solid Minerals, Gengxin Zhang, Hailiang Dong, Hongchen Jiang, Ravi K. Kukkadapu, Jinwook Kim, Dennis Eberl, Zhiqin Xu

United States Department of Energy: Publications

Iron-reducing and oxidizing microorganisms gain energy through reduction or oxidation of iron, and by doing so play an important role in the geochemical cycling of iron. This study was undertaken to investigate mineral transformations associated with microbial reduction of Fe3+ and oxidation of Fe2+ in solid minerals. A fluid sample from the 2450 m depth of the Chinese Continental Scientific Drilling project was collected, and Fe3+-reducing and Fe2+-oxidizing microorganisms were enriched. The enrichment cultures displayed reduction of Fe3+ in nontronite and ferric citrate, and oxidation of Fe2+ in vivianite, siderite, and monosulfide …

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Reduction And Long-Term Immobilization Of Technetium By Fe(Ii) Associated With Clay Mineral Nontronite, Deb Jaisi, Hailiang Dong, Andrew Plymale, James K. Fredrickson, John M. Zachara, Steve Heald, Chongxuan Liu Jan 2009

Reduction And Long-Term Immobilization Of Technetium By Fe(Ii) Associated With Clay Mineral Nontronite, Deb Jaisi, Hailiang Dong, Andrew Plymale, James K. Fredrickson, John M. Zachara, Steve Heald, Chongxuan Liu

United States Department of Energy: Publications

99Tc is formed mostly during nuclear reactions and is released into the environment during weapons testing and inadvertent waste disposal. The long half-life, high environmental mobility (as Tc(VII)O4−) and its possible uptake into the food chain cause 99Tc to be a significant environmental contaminant. In this study, we evaluated the role of Fe(II) in biologically reduced clay mineral, nontronite (NAu-2), in reducing Tc(VII) O4− to poorly soluble Tc(IV) species as a function of pH and Fe(II) concentration. The rate of Tc(VII) reduction by Fe(II) in NAu-2 was higher at neutral pH (pH 7.0) …

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Electron Donor-Dependent Radionuclide Reduction And Nanoparticle Formation By Anaeromyxobacter Dehalogenans Strain 2cp-C, Matthew J. Marshall, Alice C. Dohnalkova, David Kennedy, Andrew Plymale, Sara Thomas, Frank Löffler, Robert Sanford, John M. Zachara, James K. Fredrickson, Alexander Beliaev Jan 2009

Electron Donor-Dependent Radionuclide Reduction And Nanoparticle Formation By Anaeromyxobacter Dehalogenans Strain 2cp-C, Matthew J. Marshall, Alice C. Dohnalkova, David Kennedy, Andrew Plymale, Sara Thomas, Frank Löffler, Robert Sanford, John M. Zachara, James K. Fredrickson, Alexander Beliaev

United States Department of Energy: Publications

Anaeromyxobacter dehalogenans strain 2CP-C reduces U(VI) and Tc(VII) to U(IV)O2(s) (uraninite) and Tc(IV)O2(S) respectively. Kinetic studies with resting cells revealed that U(VI) or Tc(VII) reduction rates using H2 as electron donor exceeded those observed in acetate-amended incubations. The reduction of U(VI) by A. dehalogenans 2CP-C resulted in extracellular accumulation of ~5 nm uraninite nanoparticles in association with a lectin-binding extracellular polymeric substance (EPS). The electron donor did not affect UO2(S) nanoparticle size or association with EPS, but the utilization of acetate as the source of reducing equivalents resulted in distinct UO2(S) nanoparticle aggregates that were ~50 …

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The Roles Of Outer Membrane Cytochromes Of Shewanella And Geobacter In Extracellular Electron Transfer, Liang Shi, David J. Richardson, Zheming Wang, Sebastien Kerisit, Kevin Rosso, John M. Zachara, James K. Fredrickson Jan 2009

The Roles Of Outer Membrane Cytochromes Of Shewanella And Geobacter In Extracellular Electron Transfer, Liang Shi, David J. Richardson, Zheming Wang, Sebastien Kerisit, Kevin Rosso, John M. Zachara, James K. Fredrickson

United States Department of Energy: Publications

As key components of the electron transfer (ET) pathways used for dissimilatory reduction of solid iron [Fe(III)] (hydr)oxides, outer membrane multihaem c-type cytochromes MtrC and OmcA of Shewanella oneidensis MR-1 and OmcE and OmcS of Geobacter sulfurreducens mediate ET reactions extracellularly. Both MtrC and OmcA are at least partially exposed to the extracellular side of the outer membrane and their translocation across the outer membrane is mediated by bacterial type II secretion system. Purified MtrC and OmcA can bind Fe(III) oxides, such as haematite (α-Fe2O3), and directly transfer electrons to the haematite surface. Bindings of …

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Uranium Speciation As A Function Of Depth In Contaminated Hanford Sediments - A Micro-Xrf, Micro-Xrd, And Micro- And Bulk-Xafs Study, David Singer, John M. Zachara, Gordon Brown Jan 2009

Uranium Speciation As A Function Of Depth In Contaminated Hanford Sediments - A Micro-Xrf, Micro-Xrd, And Micro- And Bulk-Xafs Study, David Singer, John M. Zachara, Gordon Brown

United States Department of Energy: Publications

The distribution and speciation of U and Cu in contaminated vadose zone and aquifer sediments from the U.S. DOE Hanford site (300 Area) were determined using a combination of synchrotron-based micro-X-ray fluorescence (μXRF) imaging, micro-X-ray absorption near edge structure (μXANES) spectroscopy, and micro-X-ray diffraction (μXRD) techniques combined with bulk U LIII-edge X-ray absorption fine structure (XAFS) spectroscopy. Samples were collected from within the inactive North Process Pond (NPP2) at 8 ft (2.4 m, NPP2-8) depth and 12 ft (3.7 m, NPP2-12) depth in the vadose zone, and fines were isolated from turbid groundwater just below the water Table …

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Characterization Of An Electron Conduit Between Bacteria And The Extracellular Environment, Robert Hartshorne, Catherine Reardon, Daniel Ross, Jochen Nuester, Thomas Clarke, Andrew Gates, Paul Mills, James K. Fredrickson, John M. Zachara, Liang Shi, Alexander Beliaev, Matthew Marshall, Ming Tien, Susan Brantley, Julea N. Butt, David J. Richardson Jan 2009

Characterization Of An Electron Conduit Between Bacteria And The Extracellular Environment, Robert Hartshorne, Catherine Reardon, Daniel Ross, Jochen Nuester, Thomas Clarke, Andrew Gates, Paul Mills, James K. Fredrickson, John M. Zachara, Liang Shi, Alexander Beliaev, Matthew Marshall, Ming Tien, Susan Brantley, Julea N. Butt, David J. Richardson

United States Department of Energy: Publications

A number of species of Gram-negative bacteria can use insoluble minerals of Fe(III) and Mn(IV) as extracellular respiratory electron acceptors. In some species of Shewanella, deca-heme electron transfer proteins lie at the extracellular face of the outer membrane (OM), where they can interact with insoluble substrates. To reduce extracellular substrates, these redox proteins must be charged by the inner membrane/periplasmic electron transfer system. Here, we present a spectro-potentiometric characterization of a trans-OM icosa-heme complex, MtrCAB, and demonstrate its capacity to move electrons across a lipid bilayer after incorporation into proteoliposomes. We also show that a stable MtrAB …

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Modelling Evolutionary Processes In Small Populations: Not As Ideal As You Think, Robin Waples, James R. Faulkner Jan 2009

Modelling Evolutionary Processes In Small Populations: Not As Ideal As You Think, Robin Waples, James R. Faulkner

United States Department of Commerce: Staff Publications

Evolutionary processes are routinely modeled using ‘ideal’ Wright–Fisher populations of constant size N in which each individual has an equal expectation of reproductive success. In a hypothetical ideal population, variance in reproductive success (Vk) is binomial and effective population size (Ne) = N. However, in any actual implementation of the Wright– Fisher model (e.g., in a computer), Vk is a random variable and it’s realized value in any given replicate generation (Vk*) only rarely equals the binomial variance. Realized effective size (Ne*) thus also …

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Artificial Insemination In South American Camelids And Wild Equids, G. P. Adams, M. H. Ratto, C. W. Collins, D. R. Bergfelt Jan 2009

Artificial Insemination In South American Camelids And Wild Equids, G. P. Adams, M. H. Ratto, C. W. Collins, D. R. Bergfelt

United States Environmental Protection Agency: Publications

An overview of the present status of the use of artificial insemination (AI) in South American camelids and wild equids is offered. Technical aspects of semen collection, dilution and cryopreservation have limited the development and use of AI in camelid and equid species. To-date, efficiency is low but progress has been made and viable offspring have been produced through the use of AI in domestic South American camelids using both fresh and frozen semen. The origin, composition, and function of the viscous component of camelid seminal plasma remain a mystery and an obvious area for future research. A better understanding …

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Foodweb Modeling For Polychlorinated Biphenyls (Pcbs) In The Twelvemile Creek Arm Of Lake Hartwell, South Carolina, Usa, Brenda Rashleigh, M. Craig Barber, David M. Walters Jan 2009

Foodweb Modeling For Polychlorinated Biphenyls (Pcbs) In The Twelvemile Creek Arm Of Lake Hartwell, South Carolina, Usa, Brenda Rashleigh, M. Craig Barber, David M. Walters

United States Environmental Protection Agency: Publications

PCBs from the Sangamo-Weston Superfund Site near Clemson, South Carolina, USA, were released into the Twelvemile Creek Arm of Lake Hartwell until the early 1990s. Monitoring data have shown that while PCB concentration in sediments declined since 1995, PCB concentrations in fish have remained elevated, e.g., largemouth bass (Micropterus salmoides) concentrations have ranged from 5 to 10 ppm. The EPA aquatic ecosystem model AQUATOX was applied to this system to better characterize foodweb dynamics that lead to biomagnification of PCBs. The model was calibrated with observed fish biomass data. Simulated PCB loading over a 12-year period provided a …

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Comparing The Mutagenicity Of Toxaphene After Aging In Anoxic Soils And Accumulating In Fish, James C. Young, Anne D. Freeman, Robert M. Bruce, Douglas Williams, Keith Maruya Jan 2009

Comparing The Mutagenicity Of Toxaphene After Aging In Anoxic Soils And Accumulating In Fish, James C. Young, Anne D. Freeman, Robert M. Bruce, Douglas Williams, Keith Maruya

United States Environmental Protection Agency: Publications

A test program was conducted to evaluate the mutagenicity of toxaphene residuals extracted from aged soils and from fish collected in creeks near a toxaphene-contaminated site. The ultimate objective was to determine if the residual toxaphene congeners were more or less mutagenic than those in technical- grade toxaphene.The study showed that the mutagenicity of the bioaccumulated toxaphenecongeners in fish, expressed as colony revertants per mg of residual toxaphene, was no greater than that of technical-grade toxaphene.Themutagenicimpactofthetoxapheneresidualsinagedsoilstatistically was less than that for technical-grade toxaphene. Two specific congeners, a hexachlorobornane(labeled Hx-Sd) and a heptachlorobornane (labeled Hp-Sd), were found to accumulate over time …

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Finfish And Aquatic Invertebrate Pathology Resources For Now And The Future, Jan M. Spitsbergen, Vicki S. Blazer, Paul R. Bowser, Keith C. Cheng, Keith R. Cooper, Timothy K. Cooper, Salvatore Frasca Jr., David B. Groman, Claudia M. Harper, Jerry M. (Mac) Law, Gary D. Marty, Roxanna M. Smolowitz, Judy St. Leger, Douglas C. Wolf, Jeffrey C. Wolf Jan 2009

Finfish And Aquatic Invertebrate Pathology Resources For Now And The Future, Jan M. Spitsbergen, Vicki S. Blazer, Paul R. Bowser, Keith C. Cheng, Keith R. Cooper, Timothy K. Cooper, Salvatore Frasca Jr., David B. Groman, Claudia M. Harper, Jerry M. (Mac) Law, Gary D. Marty, Roxanna M. Smolowitz, Judy St. Leger, Douglas C. Wolf, Jeffrey C. Wolf

United States Environmental Protection Agency: Publications

Utilization of finfish and aquatic invertebrates in biomedical research and as environmental sentinels has grown dramatically in recent decades. Likewise the aquaculture of finfish and invertebrates has expanded rapidly worldwide as populations of some aquatic food species and threatened or endangered aquatic species have plummeted due to overharvesting or habitat degradation. This increasing intensive culture and use of aquatic species has heightened the importance of maintaining a sophisticated understanding of pathology of various organ systems of these diverse species. Yet, except for selected species long cultivated in aquaculture, pathology databases and the workforce of highly trained pathologists lag behind those …

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Combining Risks From Several Tumors Using Markov Chain Monte Carlo, Leonid Kopylev, John Fox, Chao Chen Jan 2009

Combining Risks From Several Tumors Using Markov Chain Monte Carlo, Leonid Kopylev, John Fox, Chao Chen

United States Environmental Protection Agency: Publications

In animal bioassays, tumors are often observed at multiple sites. Unit risk estimates calculated on the basis of tumor incidence at only one of these sites may underestimate the carcinogenic potential of a chemical (NRC 1994 ). Furthermore the National Research Council (NRC, 1994 ) and Bogen (1990) concluded that an approach based on counts of animals with one or more tumors (counts of “ tumor - bearing animals ” ) would tend to underestimate overall risk when tumors occur independently across sites. On independence of tumors, NRC (1994) stated: “ … a general assumption of statistical independence of tumor …

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Inter-Laboratory Control Data For Reproductive Endpoints Required In The Oppts 870.3800/Oecd 416 Reproduction And Fertility Test, M. S. Marty, B. Allen, R. E. Chapin, R. Cooper, G. P. Daston, J. A. Flaws, P. M. D. Foster, S. L. Makris, E. Mylchreest, D. Sandler, R. W. Tyl Jan 2009

Inter-Laboratory Control Data For Reproductive Endpoints Required In The Oppts 870.3800/Oecd 416 Reproduction And Fertility Test, M. S. Marty, B. Allen, R. E. Chapin, R. Cooper, G. P. Daston, J. A. Flaws, P. M. D. Foster, S. L. Makris, E. Mylchreest, D. Sandler, R. W. Tyl

United States Environmental Protection Agency: Publications

BACKGROUND: The U.S. EPA revised the Reproduction and Fertility Effects Test Guideline (OPPTS 870.3800/OECD 416) in 1998, adding numerous endpoints in an effort to incorporate new methodologies, improve the sensitivity for detecting reproductive toxicants, and more efficiently utilize study animals. Many of these new endpoints have not been used in regulatory reproductive toxicology studies prior to their inclusion in the test guidelines; thus, the Health and Environmental Sciences Institute (HESI) of the International Life Sciences Institute (ILSI) initiated the Reproductive Endpoints Project to examine the utility of these new endpoints. METHODS: This report provides a retrospective analysis of 43 multi-generation …

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Arsenate And Dimethylarsinic Acid In Drinking Water Did Not Affect Dna Damage Repair In Urinary Bladder Transitional Cells Or Micronuclei In Bone Marrow, Amy Wang, Andrew D. Kligerman, Steven D. Holladay, Douglas C. Wolf, John L. Robertson Jan 2009

Arsenate And Dimethylarsinic Acid In Drinking Water Did Not Affect Dna Damage Repair In Urinary Bladder Transitional Cells Or Micronuclei In Bone Marrow, Amy Wang, Andrew D. Kligerman, Steven D. Holladay, Douglas C. Wolf, John L. Robertson

United States Environmental Protection Agency: Publications

Arsenic is a human skin, lung, and urinary bladder carcinogen, and may act as a cocarcinogen in the skin and urinary bladder. Possible modes of action of arsenic carcinogenesis/cocarcinogenesis include oxidative stress induction and inhibition of DNA damage repair. We investigated the effects of arsenic in drinking water on DNA damage repair in urinary bladder transitional cells and on micronucleus formation in bone marrow. F344 rats were given 100 ppm arsenate [As(V)] or dimethylarsinic acid [DMA(V)] in drinking water for 1 week. The in vivo repair of cyclophosphamide (CP)-induced DNA damage resulting from a single oral gavage of CP, and …

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Safety Assessment Of Biotechnology Products For Potential Risk Of Food Allergy: Implications Of New Research, Maryjane K. Selgrade, Christal C. Bowman, Gregory S. Ladics, Laura Privalle, Susan A. Laessig Jan 2009

Safety Assessment Of Biotechnology Products For Potential Risk Of Food Allergy: Implications Of New Research, Maryjane K. Selgrade, Christal C. Bowman, Gregory S. Ladics, Laura Privalle, Susan A. Laessig

United States Environmental Protection Agency: Publications

Food allergy is a potential risk associated with use of transgenic proteins in crops. Currently, safety assessment involves consideration of the source of the introduced protein, in silico amino acid sequence homology comparisons to known allergens, physicochemical properties, protein abundance in the crop, and, when appropriate, specific immunoglobulin E binding studies. Recently conducted research presented at an International Life Sciences Institute/Health and Environmental Sciences Institute–hosted workshop adds to the scientific foundation for safety assessment of transgenic proteins in five areas: structure/activity, serum screening, animal models, quantitative proteomics, and basic mechanisms. A web-based tool is now available that integrates a database …

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Mitigation Under Section 404 Of The Clean Water Act: Where It Comes From, What It Means, Palmer Hough, Morgan Robertson Jan 2009

Mitigation Under Section 404 Of The Clean Water Act: Where It Comes From, What It Means, Palmer Hough, Morgan Robertson

United States Environmental Protection Agency: Publications

The requirement to mitigate impacts to wetlands and streams is a frequently misunderstood policy with a long and complicated history. We narrate the history of mitigation since the inception of the Clean Water Act Section 404 permit program in 1972, through struggles between the US Environmental Protection Agency and the US Army Corps of Engineers, through the emerging importance of wetland conservation on the American political landscape, and through the rise of market-based approaches to environmental policy. Mitigation, as it is understood today, was not initially foreseen as a component of the Section 404 permitting program, but was adapted from …

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Do Monk Seals Exert Top-Down Pressure In Subphotic Ecosystems?, Frank Parrish Jan 2009

Do Monk Seals Exert Top-Down Pressure In Subphotic Ecosystems?, Frank Parrish

United States Department of Commerce: Staff Publications

Patterns of subphotic fish assemblages on seamounts in the Northwestern Hawaiian Islands were identified and compared for potential structuring influences, including the bottom-up effects of regional oceanic productivity and top-down predation pressure exerted by visiting monk seals (Monachus schauinslandi). Patterns in fish size, density, and biomass were evaluated at the deep extreme (350–500 m) of the seals feeding range to avoid confounding effects of diverse shallow habitats (e.g., coral reefs). Fish number and size were used to calculate biomass density of the seamount fish assemblages that were then compared to the independent variables of summit depth, substrate type, …

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Investigation Of Growth Phases For Bottlenose Dolphins Using A Bayesian Modeling Approach, Wayne Mcfee, John Schwacke, Megan Stolen, Keith Mullin, Lori Schwacke Jan 2009

Investigation Of Growth Phases For Bottlenose Dolphins Using A Bayesian Modeling Approach, Wayne Mcfee, John Schwacke, Megan Stolen, Keith Mullin, Lori Schwacke

United States Department of Commerce: Staff Publications

The Gompertz function is the most commonly used growth function for cetacean studies. However, this function cannot represent multiple phases of growth. In this study, we present a Bayesian framework fitting parameters of a triple-logistic growth function to describe multiple phases of growth for bottlenose dolphins (Tursiops truncatus), simultaneously fitting and comparing all growth parameters between South Carolina (SC), Mississippi Sound (MSS), and Indian River Lagoon (IRL) cohorts. The fitted functions indicated a preliminary early, rapid growth phase, followed by a second phase of slower growth, and then a moderate growth spurt later in life. Growth parameters between …

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Blubber Testosterone: A Potential Marker Of Male Reproductive Status In Short-Beaked Common Dolphins, Nicholas Kellar, Marisa Trego, Corina Marks, Susan Chivers, Kerri Danil, Frederick Archer Jan 2009

Blubber Testosterone: A Potential Marker Of Male Reproductive Status In Short-Beaked Common Dolphins, Nicholas Kellar, Marisa Trego, Corina Marks, Susan Chivers, Kerri Danil, Frederick Archer

United States Department of Commerce: Staff Publications

A novel molecular technique was used to measure blubber testosterone (BT) in 114 male short-beaked common dolphins, Delphinus delphis, collected from incidental fishery bycatch and strandings. When these concentrations were compared across maturity states, the mean (± SEM) BT levels of mature D. delphis (14.3 ± 3.0 ng/g) were significantly higher than those of pubertal (2.5 ± 0.5 ng/g, P = 0.006) and immature animals (2.2 ± 0.3 ng/g, P < 0.0001). BT concentrations in mature males were significantly higher in summer months (53.9 ± 2.0 ng/g) than during the rest of the year (7.9 ± 0.69 ng/g, P < 0.0001), indicating reproductive seasonality. An analysis of BT in different anatomical locations showed that hormone concentrations were not homogenous throughout the body; the levels in the dorsal fin were significantly lower than in most other areas (F = 5.39, P = 0.043). Conversely, we found no significant differences in BT concentration with respect to subepidermal depth (F = 2.09, P = 0.146). Finally, testosterone levels in biopsies from 138 free-swimming male D. delphis, of unknown maturity state, sampled off California were found to be of concentrations similar to those from the fishery bycatch and stranding samples and revealed an …

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