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Page 1525, results 38101 - 38125

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Bedrock basins in the Sierra Nevada, Alta California
James G. Moore, Mary A. Gorden, Thomas W. Sisson
2012, California Archaeology (4) 99-122
A 360-km-long belt of more than 1,400 meter-sized granitic bedrock basins occurs at 1,200 to 2,500 m elevation on the west flank of the Sierra Nevada. The circular, smooth basins are 0.7 to 1.7 min diameter and are commonly 50 to 1,000 liters in volume. They are man-made as shown by their restricted...
Repeat surveys of spawning cisco (Coregonus artedi) in western Lake Superior: Timing, distribution and composition of spawning stocks
Daniel L. Yule, Donald R. Schreiner, Peter A. Addison, Michael J. Seider, Lori M. Evrard, Steven A. Geving, Henry R. Quinlan
2012, Advances in Limnology (63) 65-87
Acoustic (AC) and midwater trawl (MT) surveys of spawning cisco (Coregonus artedi) in Lake Superior have been combined with commercial yield to estimate exploitation. To time surveys properly, it is important to understand when adults typically arrive at spawning grounds and how numbers change as the spawning season progresses. We...
Significant motions between GPS sites in the New Madrid region: implications for seismic hazard
Arthur Frankel, Robert Smalley, J. Paul
2012, Bulletin of the Seismological Society of America (102) 479-489
Position time series from Global Positioning System (GPS) stations in the New Madrid region were differenced to determine the relative motions between stations. Uncertainties in rates were estimated using a three‐component noise model consisting of white, flicker, and random walk noise, following the methodology of Langbein, 2004. Significant motions of...
Subsidy or subtraction: how do terrestrial inputs influence consumer production in lakes?
Stuart E. Jones, Christopher T. Solomon, Brian Weidel
2012, Freshwater Reviews (5) 37-49
Cross-ecosystem fluxes are ubiquitous in food webs and are generally thought of as subsidies to consumer populations. Yet external or allochthonous inputs may in fact have complex and habitat-specific effects on recipient ecosystems. In lakes, terrestrial inputs of organic carbon contribute to basal resource availability, but can also reduce resource...
Loss and modification of habitat
Francis Lemckert, Stephen Hecnar, David S. Pilliod
2012, Book chapter, Conservation and decline of amphibians: Ecological aspects, effect of humans, and management
Amphibians live in a wide variety of habitats around the world, many of which have been modified or destroyed by human activities. Most species have unique life history characteristics adapted to specific climates, habitats (e.g., lentic, lotic, terrestrial, arboreal, fossorial, amphibious), and local conditions that provide suitable areas for reproduction,...
Ecological impacts of non-native species
David S. Pilliod, R.A. Griffiths, S.L. Kuzmin
Harold Heatwole, John W. Wilkinson, editor(s)
2012, Book chapter, Conservation and decline of amphibians: Ecological aspects, effect of humans, and management
Non-native species are considered one of the greatest threats to freshwater biodiversity worldwide (Drake et al. 1989; Allen and Flecker 1993; Dudgeon et al. 2005). Some of the first hypotheses proposed to explain global patterns of amphibian declines included the effects of non-native species (Barinaga 1990; Blaustein and Wake 1990;...
Aftershocks halted by static stress shadows
Shinji Toda, Ross S. Stein, Gregory C. Beroza, David Marsan
2012, Nature Geoscience (5) 410-413
Earthquakes impart static and dynamic stress changes to the surrounding crust. Sudden fault slip causes small but permanent—static—stress changes, and passing seismic waves cause large, but brief and oscillatory—dynamic—stress changes. Because both static and dynamic stresses can trigger earthquakes within several rupture dimensions of a mainshock, it has proven difficult...
Sexual selection and mating chronology of Lesser Prairie-Chickens
Adam C. Behney, Blake A. Grisham, Clint W. Boal, Heather A. Whitlaw, David A. Haukos
2012, Wilson Journal of Ornithology (124) 96-105
Little is known about mate selection and lek dynamics of Lesser Prairie-Chickens (Tympanuchus pallidicinctus). We collected data on male territory size and location on leks, behavior, and morphological characteristics and assessed the importance of these variables on male Lesser Prairie-Chicken mating success during spring 2008 and 2009 in the Texas...
Provisioning of nestling Dickcissels in native warm-season grass field buffers
K. L. Mitchell, Samuel K. Riffell, L. Wes Burger Jr., Francisco Vilella
2012, Wilson Journal of Ornithology (124) 298-309
We used video cameras in 2008–2009 to record provisioning activities at Dickcissel (Spiza americana) nests in and around Conservation Reserve Program field buffers in north-central Mississippi, USA. We simultaneously observed foraging flight distances of parents. Provisioning rate (P = 0.412), biomass (P = 0.161), and foraging distance (P = 0.159)...
Pyrite–sulfosalt reactions and semimetal fractionation in the Chinkuashih, Taiwan, copper–gold deposit: A 1 Ma paleo-fumarole
R.W. Henley, Byron R. Berger
2012, Geofluids (12) 245-260
The mineralized fracture system that underlay paleo-fumarole field at Chinkuashih, Taiwan has been exposed by copper–gold mining to depths of about 550 m below the paleo-surface. Its mineralogy and systematic variations in metal and semimetal (Fe, Cu, As, Sb, Bi, Hg, Cd, Sn, Zn, Pb, Se, Te, Au, Ag) concentrations provide...
Environmental and medical geochemistry in urban disaster response and preparedness
Geoffrey S. Plumlee, Suzette A. Morman, A. Cook
2012, Elements (8) 451-457
History abounds with accounts of cities that were destroyed or significantly damaged by natural or anthropogenic disasters, such as volcanic eruptions, earthquakes, wildland–urban wildfires, hurricanes, tsunamis, floods, urban firestorms, terrorist attacks, and armed conflicts. Burgeoning megacities place ever more people in the way of harm from future disasters. In addition...
Arsenic-induced biochemical and genotoxic effects and distribution in tissues of Sprague-Dawley rats
Anita K. Patlolla, Todor I. Todorov, Paul B. Tchounwou, Gijsbert van der Voet, Jose A. Centeno
2012, Microchemical Journal (105) 101-107
Arsenic (As) is a well documented human carcinogen. However, its mechanisms of toxic action and carcinogenic potential in animals have not been conclusive. In this research, we investigated the biochemical and genotoxic effects of As and studied its distribution in selected tissues of Sprague–Dawley rats. Four groups of six male...
Application of the control volume mixed finite element method to a triangular discretization
Richard L. Naff
2012, International Journal for Numerical Methods in Engineering (89) 846-868
A two‐dimensional control volume mixed finite element method is applied to the elliptic equation. Discretization of the computational domain is based in triangular elements. Shape functions and test functions are formulated on the basis of an equilateral reference triangle with unit edges. A pressure support based on...
Status and trends of prey fish populations in Lake Michigan, 2012
David B. Bunnell, Charles P. Madenjian, Timothy J. Desorcie, Melissa Jean Kostich, Kelley Smith, Jean V. Adams
2012, Report
The U.S. Geological Survey Great Lakes Science Center has conducted lake-wide surveys of the fish community in Lake Michigan each fall since 1973 using standard 12-m bottom trawls towed along contour at depths of 9 to 110 m at each of seven index transects. The resulting data on relative abundance,...
Status of pelagic prey fishes in Lake Michigan, 2012
David M. Warner, Timothy P. O’Brien, Steven A. Farha, Randall M. Claramunt, Dale Hanson
2012, Report
Acoustic surveys were conducted in late summer/early fall during the years 1992-1996 and 2001-2012 to estimate pelagic prey fish biomass in Lake Michigan. Midwater trawling during the surveys as well as target strength provided a measure of species and size composition of the fish community for use in scaling acoustic...
Status and trends of pelagic prey fishes in Lake Huron, 2012
David M. Warner, Timothy P. O’Brien, Steven A. Farha, Jeff Schaeffer, Stephen Lenart
2012, Report
The USGS Great Lakes Science Center (GLSC) conducted acoustic/midwater trawl surveys of Lake Huron during 1997 and annually during 2004-2012. The 2012 survey was conducted during September and October, and included transects in Lake Huron’s Main Basin, Georgian Bay, and North Channel. Pelagic fish density (638 fish/ha) was lower in...
Digital elevation model generation from satellite interferometric synthetic aperture radar: Chapter 5
Zhong Lu, Daniel Dzurisin, Hyung-Sup Jung, Lei Zhang, Wonjin Lee, Chang-Wook Lee
2012, Book chapter, Advances in mapping from remote sensor imagery
An accurate digital elevation model (DEM) is a critical data set for characterizing the natural landscape, monitoring natural hazards, and georeferencing satellite imagery. The ideal interferometric synthetic aperture radar (InSAR) configuration for DEM production is a single-pass two-antenna system. Repeat-pass single-antenna satellite InSAR imagery, however, also can be used to...
A Bayesian method to rank different model forecasts of the same volcanic ash cloud: Chapter 24
Roger P. Denlinger, P. Webley, Larry G. Mastin, Hans F. Schwaiger
2012, Book chapter, Lagrangian Modeling of the Atmosphere
Volcanic eruptions often spew fine ash high into the atmosphere, where it is carried downwind, forming long ash clouds that disrupt air traffic and pose a hazard to air travel. To mitigate such hazards, the community studying ash hazards must assess risk of ash ingestion for any flight path and...
Distributional changes of American martens and fishers in eastern North America, 1699-2001: Chapter 4
William B. Krohn
2012, Book chapter, Biology and Conservation of Martens, Sables, and Fishers: A New Synthesis
Contractions in the geographic distributions of the American marten ( Martes americana) and fi sher ( M. pennanti) in eastern North America south of the St. Lawrence River between Colonial times (ca. 1650–1800) and the fi sher’s recent range expansion (ca. 1930–present) are well documented, but causal factors in these...
Establishment of sentinel sampling sites to monitor changes in water and sediment quality and biota related to visitor use at Lake Powell, Arizona and Utah, 2004-2006
Robert J. Hart, Howard E. Taylor, G.M. Anderson
2012, Open-File Report 2012-1237
Twenty sentinel sampling sites were established and sampled during 2004–06 at Lake Powell, Arizona and Utah, by the U.S. Geological Survey and the National Park Service—Glen Canyon National Recreation Area. The sentinel sampling sites provide sampling locations on Lake Powell, the Nation’s second largest reservoir that can be visited and...
Analysis of host genetic diversity and viral entry as sources of between-host variation in viral load
Andrew R. Wargo, Alison M. Kell, Robert J. Scott, Gary H. Thorgaard, Gael Kurath
2012, Virus Research (165) 71-80
Little is known about the factors that drive the high levels of between-host variation in pathogen burden that are frequently observed in viral infections. Here, two factors thought to impact viral load variability, host genetic diversity and stochastic processes linked with viral entry into the host, were examined. This work...
Observed source parameters for dynamic rupture with non-uniform initial stressand relatively high fracture energy
Nicholas M. Beeler, Brian D. Kilgore, Arthur F. McGarr, Jon Peter B. Fletcher, John R. Evans, Steven R. Baker
2012, Journal of Structural Geology (38) 77-89
We have conducted dynamic rupture propagation experiments to establish the relations between in-source stress drop, fracture energy and the resulting particle velocity during slip of an unconfined 2 m long laboratory fault at normal stresses between 4 and 8 MPa. To produce high fracture energy in the source we use a...