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Articles 11131 - 11160 of 14126
Full-Text Articles in Entire DC Network
2007 Plant Community Survey Of The Wildcat Hills Banner & Scotts Bluff Counties, Nebraska, Robert F. Steinauer
2007 Plant Community Survey Of The Wildcat Hills Banner & Scotts Bluff Counties, Nebraska, Robert F. Steinauer
Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts
To facilitate conservation efforts within the BUL, vegetation surveys were conducted from July 5 to August 30, 2007 to provide additional information concerning the distribution and quality of native plant community and rare plant species occurrences within the area.
Approximately 50,000 acres were surveyed representing approximately one third of the Wildcat Hills west of Hubbard’s Gap Road. Landowners were contacted and permission to access their properties granted prior to field surveys. Nebraska Natural Heritage Program (NHHP) Ecological Community Survey Forms were completed to document plant communities, and NHHP Rare Plant Survey Forms were completed to document rare plants (S1 and …
Subfamily Phyllostominae Gray, 1825 From Mammals Of South America, Stephen L. Williams, Hugh H. Genoways
Subfamily Phyllostominae Gray, 1825 From Mammals Of South America, Stephen L. Williams, Hugh H. Genoways
University of Nebraska State Museum: Mammalogy Papers
The subfamily Phyllostominae is distributed from the southern United States (Arizona, California, and southern Nevada), southward into northern Argentina, Paraguay, and southern Brazil. South American phyllostomines are primarily restricted to the mainland, but also occur on a few major islands off the coast of South America, such as Margarita Island (Venezuela), Trinidad and Tobago, and the Netherlands Antilles, as well as the Greater and Lesser Antilles. The number of genera and species recognized in the subfamily depends on the taxonomic interpretations of the content of the genera Lophostoma, Micronycteris, Mimon, Phyllostomus, and Tonatia. In near agreement with the …
Toward Common Nomenclature And Definitions For Natural Science Professional Collections-Related Positions, Paisley S. Cato, Hugh H. Genoways
Toward Common Nomenclature And Definitions For Natural Science Professional Collections-Related Positions, Paisley S. Cato, Hugh H. Genoways
University of Nebraska State Museum: Programs Information
Analysis of recent literature and experience with professional positions in several institutions provided the basis for proposing a basic grouping of titles for positions relating to the natural sciences collections profession. Six groups ore proposed with recommendations for education, experience, knowledge, and skills to support the key responsibilities of the positions. Discussions and critiques of these groupings ore anticipated to refine and ultimately result in a standardized nomenclature for natural science collections-related positions.
Planning The Future Workforce Of Natural Science Research Collections: A Review Of Graduate Academic Programs In The United States, Stephen L. Williams, Hugh H. Genoways
Planning The Future Workforce Of Natural Science Research Collections: A Review Of Graduate Academic Programs In The United States, Stephen L. Williams, Hugh H. Genoways
University of Nebraska State Museum: Programs Information
Selected literature and Internet sites were used to identify universities that provide graduate academic degrees relevant to the management and care of natural science research collections. Twelve universities with degree programs not dedicated to the arts or humanity fields were selected for closer evaluation. By analyzing the courses offered in museology and the natural sciences at each university, seven universities were identified as currently in a position to provide some level of education and training needed by the future workforce of natural science research collections. However, only two universities stood out as being in the best position to serve most …
Nebraska Earth Systems Education Network – Winter 2006/07
Nebraska Earth Systems Education Network – Winter 2006/07
Nebraska Earth Systems Education Network
Content:
Second Lab Earth Course to Study Natural Resources by Karen Pietsch
Teacher Spotlight: Bob Fuerer By Karen Pietsch
Carbon Offsets Offer Environmental Penance, Promotion By Karen Pietsch
Lab Earth Concepts Carried into Classrooms By Karen Pietsch
‘Advanced Scholars’ Helps High School- College Transition By Karen Pietsch
New Masters of Arts Option Focuses on Applied Science by Karen Pietsch
C3–C4 Composition And Prior Carbon Dioxide Treatment Regulate The Response Of Grassland Carbon And Water Fluxes To Carbon Dioxide, H. W. Polley, W. A. Dugas, P. C. Mielnick, H. B. Johnson
C3–C4 Composition And Prior Carbon Dioxide Treatment Regulate The Response Of Grassland Carbon And Water Fluxes To Carbon Dioxide, H. W. Polley, W. A. Dugas, P. C. Mielnick, H. B. Johnson
United States Department of Agriculture-Agricultural Research Service / University of Nebraska-Lincoln: Faculty Publications
During May, July and October 2000, we measured the effects of temporarily increasing or decreasing CO2 concentration by 150–200 μmol mol−1 on daytime net ecosystem CO2 exchange (NEE) and water flux (evapotranspiration, ET) of C3–C4 grassland in central Texas, USA that had been exposed for three growing seasons to a CO2 gradient from 200 to 560 μmol mol−1. Grassland grown at subambient CO2 (< 365 μmol mol−1) was exposed for 2 days to an elevated CO2 gradient (> 365 μmol mol−1). Grassland grown at elevated CO2 was …
The Role Of Meaning In Past-Tense Inflection: Evidence From Polysemy And Denominal Derivation, Shoba Bandi-Rao, Gregory L. Murphy
The Role Of Meaning In Past-Tense Inflection: Evidence From Polysemy And Denominal Derivation, Shoba Bandi-Rao, Gregory L. Murphy
Publications and Research
Although English verbs can be either regular (walk-walked) or irregular (sing-sang), “denominal verbs” that are derived from nouns, such as the use of the verb ring derived from the noun a ring, take the regular form even if they are homophonous with an existing irregular verb: The soldiers ringed the city rather than *The soldiers rang the city. Is this regularization due to a semantic difference from the usual verb, or is it due to the application of the default rule, namely VERB + -ed suffix? To gain a new source of insight into …
Impacts Of Modern Molecular Genetic Techniques On Conservation Biology, Eli Geffen, Gordon Luikart, Robin Waples
Impacts Of Modern Molecular Genetic Techniques On Conservation Biology, Eli Geffen, Gordon Luikart, Robin Waples
United States Department of Commerce: Staff Publications
Conservation biology strives to conserve biodiversity and biological processes in ecosystems, of which genetic variation is a key component. Genetic variation is the underlying foundation of higher levels of biodiversity (e.g. populations and species). Without genetic variation, populations could not evolve and adapt to future environmental changes. Because DNA (deoxyribonucleic acid) is fundamental to all biological systems, the practice of conservation often requires genetic studies. Beyond the measurement and conservation of genetic variation per se, the uses of molecular genetic techniques in conservation biology include:
1. identification of individuals, species, populations and conservation units;
2. detection of hybrid zones …
A Dwarf Form Of Killer Whale In Antarctica, Robert L. Pitman, Wayne L. Perryman, Don Leroi, Erik Eilers
A Dwarf Form Of Killer Whale In Antarctica, Robert L. Pitman, Wayne L. Perryman, Don Leroi, Erik Eilers
United States Department of Commerce: Staff Publications
In the early 1980s, 2 groups of Soviet scientists independently described 1, possibly 2 new dwarf species of killer whales (Orcinus) from Antarctica. We used aerial photogrammetry to determine total length (TL) of 221 individual Type C killer whales—a fish-eating ecotype that inhabits dense pack ice—in the southern Ross Sea in January 2005. We confirmed it as one of the smallest killer whales known: TL of adult females (with calves) averaged 5.2 m ± 0.23 SD (n = 33); adult males averaged 5.6 ± 0.32 m (n = 65), with the largest measuring 6.1 m. Female Type A …
Estimating The Number Of Whales Entering Trade Using Dna Profiling And Capture-Recapture Analysis Of Market Products, C. Scott Baker, Justin G. Cooke, Shane Lavery, Merel L. Dalebout, Robert L. Brownell Jr., Yong-Un Ma, Naoko Funahashi, Colm Carraher
Estimating The Number Of Whales Entering Trade Using Dna Profiling And Capture-Recapture Analysis Of Market Products, C. Scott Baker, Justin G. Cooke, Shane Lavery, Merel L. Dalebout, Robert L. Brownell Jr., Yong-Un Ma, Naoko Funahashi, Colm Carraher
United States Department of Commerce: Staff Publications
Surveys of commercial markets combined with molecular taxonomy (i.e. molecular monitoring) provide a means to detect products from illegal, unregulated and/or unreported (IUU) exploitation, including the sale of fisheries bycatch and wild meat (bushmeat). Capture-recapture analyses of market products using DNA profiling have the potential to estimate the total number of individuals entering the market. However, these analyses are not directly analogous to those of living individuals because a ‘market individual’ does not die suddenly but, instead, remains available for a time in decreasing quantities, rather like the exponential decay of a radioactive isotope. Here we use mitochondrial DNA (mtDNA) …
The Whaling Issue: Conservation, Confusion, And Casuistry, Phillip J. Clapham, Simon Childerhouse, Nicolas J. Gales, Lorenzo Rojas-Bracho, Michael F. Tillman, Robert L. Brownell Jr.
The Whaling Issue: Conservation, Confusion, And Casuistry, Phillip J. Clapham, Simon Childerhouse, Nicolas J. Gales, Lorenzo Rojas-Bracho, Michael F. Tillman, Robert L. Brownell Jr.
United States Department of Commerce: Staff Publications
Morishita’s “multiple analysis”of the whaling issue [Morishita J. Multiple analysis of the whaling issue: Understanding the dispute by a matrix. Marine Policy 2006;30:802–8] is essentially a restatement of the Government of Japan’s whaling policy, which confuses the issue through selective use of data, unsubstantiated facts, and the vilification of opposing perspectives. Here, we deconstruct the major problems with Morishita’s article and provide an alternative view of the whaling dispute. For many people in this debate, the issue is not that some whales are not abundant, but that the whaling industry cannot be trusted to regulate itself or to honestly assess …
Space–Time Zero-Inflated Count Models Of Harbor Seals, Jay M. Ver Hoef, John K. Jansen
Space–Time Zero-Inflated Count Models Of Harbor Seals, Jay M. Ver Hoef, John K. Jansen
United States Department of Commerce: Staff Publications
Environmental data are spatial, temporal, and often come with many zeros. In this paper, we included space–time random effects in zero-inflated Poisson (ZIP) and ‘hurdle’ models to investigate haulout patterns of harbor seals on glacial ice. The data consisted of counts, for 18 dates on a lattice grid of samples, of harbor seals hauled out on glacial ice in Disenchantment Bay, near Yakutat, Alaska. A hurdle model is similar to a ZIP model except it does not mix zeros from the binary and count processes. Both models can be used for zero-inflated data, and we compared space–time ZIP and hurdle …
Polyamine Permeation And Rectification Of Kir4.1 Channels, Yuri V. Kucheryavykh, Wade L. Pearson, Harley T. Kurata, Misty J. Eaton, Serguei N. Skatchkov, Colin G. Nichols
Polyamine Permeation And Rectification Of Kir4.1 Channels, Yuri V. Kucheryavykh, Wade L. Pearson, Harley T. Kurata, Misty J. Eaton, Serguei N. Skatchkov, Colin G. Nichols
Open Access Publications
No abstract provided.
Clinical Significance Of Αii-Spectrin Breakdown Products In Cerebrospinal Fluid After Severe Traumatic Brain Injury, Jose A. Pineda, Stephen B. Lewis, Alex B. Valadka, Linda Papa, H. Julia Hannay, Shelley C. Heaton, Jason A. Demery, Ming Cheng Liu, Jada M. Aikman, Veronica Akle, Gretchen M. Brophy, Joseph J. Tepas Iii, Kevin K. W. Wang, Claudia S. Robertson, Ronald L. Hayes
Clinical Significance Of Αii-Spectrin Breakdown Products In Cerebrospinal Fluid After Severe Traumatic Brain Injury, Jose A. Pineda, Stephen B. Lewis, Alex B. Valadka, Linda Papa, H. Julia Hannay, Shelley C. Heaton, Jason A. Demery, Ming Cheng Liu, Jada M. Aikman, Veronica Akle, Gretchen M. Brophy, Joseph J. Tepas Iii, Kevin K. W. Wang, Claudia S. Robertson, Ronald L. Hayes
Open Access Publications
No abstract provided.
Temporal Differences In The Hydrologic Regime Of The Lower Platte River, Nebraska, 1895–2006, Daniel Ginting, Ronald B. Zelt, Joshua I. Linard
Temporal Differences In The Hydrologic Regime Of The Lower Platte River, Nebraska, 1895–2006, Daniel Ginting, Ronald B. Zelt, Joshua I. Linard
United States Geological Survey: Publications
In cooperation with the Lower Platte South Natural Resources District for a collaborative study of the cumulative effects of water and channel management practices on stream and riparian ecology, the U.S. Geological Survey (USGS) compiled, analyzed, and summarized hydrologic information from long-term gaging stations on the lower Platte River to determine any significant temporal differences among six discrete periods during 1895-2006 and to interpret any significant changes in relation to changes in climatic conditions or other factors. A subset of 171 examined hydrologic indices (HIs) were selected for use as indices that (1) included most of the variance in the …
Simulations Of Ground-Water Flow, Transport, Age, And Particle Tracking Near York, Nebraska, For A Study Of Transport Of Anthropogenic And Natural Contaminants (Tanc) To Public-Supply Wells, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Hornberger
Simulations Of Ground-Water Flow, Transport, Age, And Particle Tracking Near York, Nebraska, For A Study Of Transport Of Anthropogenic And Natural Contaminants (Tanc) To Public-Supply Wells, Brian R. Clark, Matthew K. Landon, Leon J. Kauffman, George Hornberger
United States Geological Survey: Publications
The U.S. Geological Survey (USGS) is committed to providing the Nation with credible scientific information that helps to enhance and protect the overall quality of life and that facilitates effective management of water, biological, energy, and mineral resources (http://www.usgs.gov/). Information on the Nation’s water resources is critical to ensuring long-term availability of water that is safe for drinking and recreation and is suitable for industry, irrigation, and fish and wildlife. Population growth and increasing demands for water make the availability of that water, now measured in terms of quantity and quality, even more essential to the long-term sustainability of our …
The Influence Of Sublacustrine Hydrothermal Vent Fluids On The Geochemistry Of Yellowstone Lake, Laurie S. Balistrieri, Wayne C. Shanks Iii, Russell L. Cuhel, Carmen Aguilar, J. Val Klump
The Influence Of Sublacustrine Hydrothermal Vent Fluids On The Geochemistry Of Yellowstone Lake, Laurie S. Balistrieri, Wayne C. Shanks Iii, Russell L. Cuhel, Carmen Aguilar, J. Val Klump
United States Geological Survey: Publications
The geochemical composition of Yellowstone Lake water is strongly influenced by sublacustrine hydrothermal vent activity. The evidence for this conclusion is twofold. First, mass-balance calculations indicate that the outflow from Yellowstone Lake is enriched in dissolved As, B, Cl, Cs, Ge, Li, Mo, Sb, and W relative to inflowing waters. Calculations involving stable isotopes of hydrogen and oxygen (δD and δ18O, respectively) and mass-balances indicate about 13 percent evapoconcentration in the lake, which is inadequate to account for the enrichment of these elements in the water column. Second, linear relationships between the concentration of Cl and many other elements in …
Hydrothermally Altered Rock And Hot-Spring Deposits At Yellowstone National Park—Characterized Using Airborne Visible- And Infrared-Spectroscopy Data, K. Eric Livo, Fred A. Kruse, Roger N. Clark, Raymond F. Kokaly, W. C. Shanks Iii
Hydrothermally Altered Rock And Hot-Spring Deposits At Yellowstone National Park—Characterized Using Airborne Visible- And Infrared-Spectroscopy Data, K. Eric Livo, Fred A. Kruse, Roger N. Clark, Raymond F. Kokaly, W. C. Shanks Iii
United States Geological Survey: Publications
The hydrothermal system in Yellowstone National Park has created altered rock and hot-spring deposits that were mapped using AVIRIS (airborne visible and infrared imaging spectrometer) data. The mapped minerals are indicative of the geologic processes and environments that controlled their formation. Ongoing volcanic activity is expressed at the surface by geothermal features, earthquakes, and geologically recent caldera formation. Precipitated minerals such as siliceous sinter and travertine on the surface are derived from chloride-rich alkaline solutions that are leaching silica and calcite from the underlying country rock. Siliceous sinter and montmorillonite are associated with hydrothermal systems abundant in hot water, whereas …
Investigations Of The Effects Of Synthetic Chemicals On The Endocrine System Of Common Carp In Lake Mead, Nevada And Arizona, Michael R. Rosen, Steven L. Goodbred, Reynaldo Patiño, Thomas J. Leiker, Erik Orsak
Investigations Of The Effects Of Synthetic Chemicals On The Endocrine System Of Common Carp In Lake Mead, Nevada And Arizona, Michael R. Rosen, Steven L. Goodbred, Reynaldo Patiño, Thomas J. Leiker, Erik Orsak
United States Geological Survey: Publications
Lake Mead is the largest reservoir by volume in the United States and was created by the construction of the 221-meter high Hoover Dam in 1935 at Black Canyon on the lower Colorado River between Nevada and Arizona (fig. 1). Inflows of water into the lake include three rivers, Colorado, Virgin, and Muddy; as well as Las Vegas Wash, which is now perennial because of discharges from municipal wastewater treatment plants (Covay and Leiker, 1998) and urban stormwater runoff. As the population within the Las Vegas Valley began to increase in the 1940s, the treated effluent volume also has increased …
Applications Of Trace-Element And Stable-Isotope Geochemistry To Wildlife Issues, Yellowstone National Park And Vicinity, Maurice A. Chaffee, Wayne C. Shanks Iii, Robert O. Rye, Charles C. Shwartz, Monique G. Adams, Robert R. Carlson, James G. Crock, Pamela A. Gemery-Hill, Kerry A. Gunther, Cynthia L. Kester, Harley D. King, Shannon R. Podruzny
Applications Of Trace-Element And Stable-Isotope Geochemistry To Wildlife Issues, Yellowstone National Park And Vicinity, Maurice A. Chaffee, Wayne C. Shanks Iii, Robert O. Rye, Charles C. Shwartz, Monique G. Adams, Robert R. Carlson, James G. Crock, Pamela A. Gemery-Hill, Kerry A. Gunther, Cynthia L. Kester, Harley D. King, Shannon R. Podruzny
United States Geological Survey: Publications
Reconnaissance investigations have been conducted to identify how geochemical techniques can be applied to biological studies to assist wildlife management in and near Yellowstone National Park (the Park). Many elements (for example, As, B, Be, Ce, Cl, Cs, F, Hg, K, Li, Mo, Rb, S, Sb, Si, and W) are commonly enriched in (1) thermal waters in the Yellowstone area, (2) rocks altered by these waters, (3) sinter and travertine deposits, and (4) soils and stream sediments derived from these rocks. Some of these elements, such as As, F, Hg, and Mo, may be toxic to wildlife and could be …
Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May
Concentrations Of Metals In Aquatic Invertebrates From The Ozark National Scenic Riverways, Missouri, Christopher J. Schmitt, William G. Brumbaugh, John M. Besser, Thomas W. May
United States Geological Survey: Publications
This report summarizes the findings of a study conducted as a pilot for part of a park-wide monitoring program being developed for the Ozark National Scenic Riverways (ONSR) of southeastern Missouri. The objective was to evaluate using crayfish (Orconectes spp.) and Asian clam (Corbicula fluminea) for monitoring concentrations of metals associated with lead-zinc mining. Lead-zinc mining presently (2007) occurs near the ONSR and additional mining has been proposed. Three composite samples of each type (crayfish and Asian clam), each comprising ten animals of approximately the same size, were collected during late summer and early fall of 2005 …
Geochemical Controls On Contaminant Uranium In Vadose Hanford Formation Sediments At The 200 Area And 300 Area, Hanford Site, Washington, James Mckinley, John M. Zachara, Jiamin Wan, David Mccready, Steven M. Heald
Geochemical Controls On Contaminant Uranium In Vadose Hanford Formation Sediments At The 200 Area And 300 Area, Hanford Site, Washington, James Mckinley, John M. Zachara, Jiamin Wan, David Mccready, Steven M. Heald
United States Department of Energy: Publications
Long-term historic spills of uranium at the 300 Area fuel fabrication site (58,000 kg of disposed uranium over 32 yr) and at the 200 East Area BX tank farm (7000 kg of spilled uranium in one event), both within the Hanford formation in the Hanford Site, Washington State, were investigated by subsurface sampling and subsequent microscale investigations of excavated samples. The 200 Area sediments contained uranyl silicate mineralization (sodium boltwoodite) in restrictive microfractures in granitic clasts, in the vadose zone over a narrow range in depth. Well logging and column experiments indicated that tank wastes migrated deeper than observed in …
Hanford Site Vadose Zone Studies: An Overview, G. W. Gee, M. Oostrom, M. D. Freshley, M. L. Rockhold, John M. Zachara
Hanford Site Vadose Zone Studies: An Overview, G. W. Gee, M. Oostrom, M. D. Freshley, M. L. Rockhold, John M. Zachara
United States Department of Energy: Publications
Large quantities of radioactive and chemical wastes resulting from Pu production for nuclear weapons are located in the vadose zone at the USDOE’s Hanford Site, north of Richland, WA. The vadose zone here is characterized by often highly stratified glacial-fluvial sediments that give rise to complex subsurface-flow paths that contribute to uncertainty of contaminant fate and transport. Research efforts have focused on answering questions of contaminant transport from the viewpoint of geologic, biologic, geochemical, and hydrologic controls. This special section highlights key research topics concerning vadose zone problems at the Hanford Site. Research indicates that some of the contaminant species …
Florida Seagrass Habitat Evaluation: A Comparative Survey For Chemical Quality, Michael A. Lewis, Darrin D. Dantin, Cynthia A. Chancy, Kathryn Abel, Christopher G. Lewis
Florida Seagrass Habitat Evaluation: A Comparative Survey For Chemical Quality, Michael A. Lewis, Darrin D. Dantin, Cynthia A. Chancy, Kathryn Abel, Christopher G. Lewis
United States Environmental Protection Agency: Publications
Contaminant concentrations were determined for media associated with 13 Florida seagrass beds. Concentrations of 10 trace metals were more commonly detected in surface water, sediment and two seagrass species than PAHs, pesticides and PCBs. Concentrations of copper and arsenic in surface water exceeded Florida aquatic life criteria more frequently than other trace elements. Total organic carbon, mercury, chromium, zinc, total chlordane, total PAHs, total PCBs, DDD and DDE were significantly greater in seagrass-rooted sediments than adjacent non-vegetated sediments. Total DDT, DDD, DDE, total chlordane, arsenic, copper and nickel exceeded proposed sediment quality guidelines at six of 13 grass beds. Pesticides, …
Convergence Of Peridynamics To Classical Elasticity Theory, S. A. Silling, R. B. Lehoucq
Convergence Of Peridynamics To Classical Elasticity Theory, S. A. Silling, R. B. Lehoucq
United States Department of Energy: Publications
The peridynamic model of solid mechanics is a nonlocal theory containing a length scale. It is based on direct interactions between points in a continuum separated from each other by a finite distance. The maximum interaction distance provides a length scale for the material model. This paper addresses the question of whether the peridynamic model for an elastic material reproduces the classical local model as this length scale goes to zero. We show that if the motion, constitutive model, and any nonhomogeneities are sufficiently smooth, then the peridynamic stress tensor converges in this limit to a Piola-Kirchhoff stress tensor that …
Kinetics Of Reductive Dissolution Of Hematite By Bioreduced Anthraquinone-2,6-Disulfonate, Chongxuan Liu, John M. Zachara, Nancy Foster, Janae Strickland
Kinetics Of Reductive Dissolution Of Hematite By Bioreduced Anthraquinone-2,6-Disulfonate, Chongxuan Liu, John M. Zachara, Nancy Foster, Janae Strickland
United States Department of Energy: Publications
The reductive dissolution of hematite (α-Fe2O3) was investigated in a flow-through system using AH2DS, a reduced form of anthraquinone-2,6-disulfonate (AQDS), which is often used as a model electron shuttling compound in studies of dissimilatory microbial reduction of iron oxides. Influent flow rate, pH, and Fe(II) and phosphate concentrations were varied to investigate the redox kinetics in a flow-through reactor. The hematite reduction rates decreased with increasing pH from 4.5 to 7.6 and decreased with decreasing flow rate. The rates also decreased with increasing influent concentration of Fe(II) or phosphate that formed surface complexes at the experimental …
Respiration Of Metal (Hydr)Oxides By Shewanella And Geobacter: A Key Role For Multihaem C-Type Cytochromes, Liang Shi, Thomas C. Squier, John M. Zachara, James K. Fredrickson
Respiration Of Metal (Hydr)Oxides By Shewanella And Geobacter: A Key Role For Multihaem C-Type Cytochromes, Liang Shi, Thomas C. Squier, John M. Zachara, James K. Fredrickson
United States Department of Energy: Publications
Dissimilatory reduction of metal (e.g. Fe, Mn) (hydr)oxides represents a challenge for microorganisms, as their cell envelopes are impermeable to metal (hydr)oxides that are poorly soluble in water. To overcome this physical barrier, the Gram-negative bacteria Shewanella oneidensis MR-1 and Geobacter sulfurreducens have developed electron transfer (ET) strategies that require multihaem c-type cytochromes (c-Cyts). In S. oneidensis MR-1, multihaem c-Cyts CymA and MtrA are believed to transfer electrons from the inner membrane quinone/quinol pool through the periplasm to the outer membrane. The type II secretion system of S. oneidensis MR-1 has been implicated in the reduction of metal …
Adaptive Harvest Management: 2007 Hunting Season
Adaptive Harvest Management: 2007 Hunting Season
United States Fish and Wildlife Service: Publications
The process of setting waterfowl hunting regulations is conducted annually in the United States (Blohm 1989). This process involves a number of meetings where the status of waterfowl is reviewed by the agencies responsible for setting hunting regulations. In addition, the U.S. Fish and Wildlife Service (USFWS) publishes proposed regulations in the Federal Register to allow public comment. This document is part of a series of reports intended to support development of harvest regulations for the 2007 hunting season. Specifically, this report is intended to provide waterfowl managers and the public with information about the use of adaptive harvest management …
American Woodcock Population Status, 2007, James R. Kelley Jr., Rebecca D. Rau
American Woodcock Population Status, 2007, James R. Kelley Jr., Rebecca D. Rau
United States Fish and Wildlife Service: Publications
Singing-ground Survey data indicated that the numbers of displaying American woodcock (Scolopax minor) in the Eastern Region in 2007 declined 11.6% from 2006; however, the Central Region was unchanged. There was no significant trend in woodcock heard in either the Eastern or Central Region during 1997-07. This represents the fourth consecutive year that the 10-year trend estimate did not indicate a significant decline. There were long-term (1968-07) declines of 2.0% per year in the Eastern Region and 1.8% per year in the Central Region. The 2006 recruitment index for the U.S. portion of the Eastern Region (1.5 immatures …
Valentine National Wildlife Refuge 2007
Valentine National Wildlife Refuge 2007
United States Fish and Wildlife Service: Publications
INTRODUCTION
Valentine National Wildlife Refuge (NWR) was established on August 4, 1935 under the Migratory Bird Conservation Act by Executive Order 7142. The purpose of the refuge as stated in the executive order is “as a refuge and breeding ground for migratory birds and other wildlife.” Acquisition funding came from Duck Stamp sales and the Emergency Conservation Fund Of 1933.
The 71,772-acre Valentine NWR is located in the Sandhills of north-central Nebraska. The Sandhills contain the largest remaining stands of mid and tall grass native prairie left in North America. The refuge is a unique and ecologically important component of …