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Page 1414, results 35326 - 35350

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Automated quantitative micro-mineralogical characterization for environmental applications
Kathleen S. Smith, K.O. Hoal, Katherine Walton-Day, J.G. Stammer, K. Pietersen
2013, Conference Paper
Characterization of ore and waste-rock material using automated quantitative micro-mineralogical techniques (e.g., QEMSCAN® and MLA) has the potential to complement traditional acid-base accounting and humidity cell techniques when predicting acid generation and metal release. These characterization techniques, which most commonly are used for metallurgical, mineral-processing, and geometallurgical applications, can be...
Defining groundwater age
T. Torgersen, R. Purtschert, F. M. Phillips, Niel Plummer, W. E. Sanford, A. Suckow
2013, Book chapter, Isotope Methods for Dating Old Groundwater
This book investigates applications of selected chemical and isotopic substances that can be used to recognize and interpret age information pertaining to ‘old’ groundwater (defined as water that was recharged on a timescale from approximately 1000 to more than 1 000 000 a). However, as discussed below, only estimates of...
Rediscovering traditional vegetation management in preserves: trading experiences between cultures and continents
Beth A. Middleton
2013, Biological Conservation (158) 271-279
Land managers are grappling with massive changes in vegetation structure, particularly in protected areas formerly subjected to fire and grazing. The objective of this review was to compare notes on the historical and current management of ecosystems around the world (especially in wet to dry grasslands in the Americas, Australia,...
Characterization and conceptualization of groundwater flow systems
Niel Plummer, W. E. Sanford, P. D. Glynn
2013, Book chapter, Isotope Methods for Dating Old Groundwater
This chapter discusses some of the fundamental concepts, data needs and approaches that aid in developing a general understanding of a groundwater system. Principles of the hydrological cycle are reviewed; the processes of recharge and discharge in aquifer systems; types of geological, hydrological and hydraulic data needed to describe the...
The role of virulence for in vivo superinfection fitness of a vertebrate RNA virus
Alison M. Kell, Andrew R. Wargo, Gael Kurath
2013, Journal of Virology (87) 8145-8157
We have developed a novel, in vivo superinfection fitness assay to examine superinfection dynamics and the role of virulence in superinfection fitness. This assay involves controlled, sequential infections of a natural, vertebrate host, Oncorhynchus mykiss (rainbow trout), with variants of a co-evolved viral pathogen, infectious hematopoietic necrosis virus (IHNV). Intervals...
Colonization of steelhead in a natal stream after barrier removal
Dana E. Weigel, Patrick J. Connolly, Kyle D. Martens, Madison S. Powell
2013, Transactions of the American Fisheries Society (142) 920-930
Colonization of vacant habitats is an important process for supporting the long-term persistence of populations and species. We used a before–after experimental design to follow the process of colonization by steelhead Oncorhynchus mykiss (anadromous Rainbow Trout) at six monitoring sites in a natal stream, Beaver Creek, after the modification or...
Tracking sedimentation from the historic A.D. 2011 Mississippi River flood in the deltaic wetlands of Louisiana, USA
Nicole S. Khan, Benjamin P. Horton, Karen L. McKee, Douglas Jerolmack, Federico Falcini, Mihaela D. Enache, Christopher H. Vane
2013, Geology (41) 391-394
Management and restoration of the Mississippi River deltaic plain (southern United States) and associated wetlands require a quantitative understanding of sediment delivery during large flood events, past and present. Here, we investigate the sedimentary fingerprint of the 2011 Mississippi River flood across the Louisiana coast (Atchafalaya Delta, Terrebonne, Barataria, and...
Uranium quantification in semen by inductively coupled plasma mass spectrometry
Todor I. Todorov, John W. Ejnik, Gustavo S. Guandalini, Hanna Xu, Dennis Hoover, Larry W. Anderson, Katherine Squibb, Melissa A. McDiarmid, Jose A. Centeno
2013, Journal of Trace Elements in Medicine and Biology (27) 2-6
In this study we report uranium analysis for human semen samples. Uranium quantification was performed by inductively coupled plasma mass spectrometry. No additives, such as chymotrypsin or bovine serum albumin, were used for semen liquefaction, as they showed significant uranium content. For method validation we spiked 2 g aliquots of pooled...
Inferring fault rheology from low-frequency earthquakes on the San Andreas
Nicholas M. Beeler, Amanda Thomas, Roland Bürgmann, David R. Shelly
2013, Journal of Geophysical Research (118) 5976-5990
Families of recurring low-frequency earthquakes (LFEs) within nonvolcanic tremor (NVT) on the San Andreas fault in central California show strong sensitivity to shear stress induced by the daily tidal cycle. LFEs occur at all levels of the tidal shear stress and are in phase with the very small, ~400 Pa, stress...
The role of airborne mineral dusts in human disease
Suzette A. Morman, Geoffrey S. Plumlee
2013, Aeolian Research (9) 203-212
Exposure to fine particulate matter (PM) is generally acknowledged to increase risk for human morbidity and mortality. However, particulate matter (PM) research has generally examined anthropogenic (industry and combustion by-products) sources with few studies considering contributions from geogenic PM (produced from the Earth by natural processes, e.g., volcanic ash, windborne...
Multi-species call-broadcast improved detection of endangered Yuma clapper rail compared to single-species call-broadcast
Christopher P. Nadeau, Courtney J. Conway, Linden Piest, William P. Burger
2013, Wetlands (33) 699-706
Broadcasting calls of marsh birds during point-count surveys increases their detection probability and decreases variation in the number of birds detected across replicate surveys. However, multi-species monitoring using call-broadcast may reduce these benefits if birds are reluctant to call once they hear broadcasted calls of other species. We compared a...
Interactions between brown bears and chum salmon at McNeil River, Alaska
Joshua Peirce, Edward O. Otis, Mark S. Wipfli, Erich H. Follmann
2013, Ursus (24) 42-53
Predation on returning runs of adult salmon (Oncorhynchus spp.) can have a large influence on their spawning success. At McNeil River State Game Sanctuary (MRSGS), Alaska, brown bears (Ursus arctos) congregate in high numbers annually along the lower McNeil River to prey upon returning adult chum salmon (O. keta). Low...
Groundwater quality in western New York, 2011
James E. Reddy
2013, Open-File Report 2013-1095
Water samples collected from 16 production wells and 15 private residential wells in western New York from July through November 2011 were analyzed to characterize the groundwater quality. Fifteen of the wells were finished in sand and gravel aquifers, and 16 were finished in bedrock aquifers. Six of the 31...
Evidence of territoriality and species interactions from spatial point-pattern analyses of subarctic-nesting geese
Matthew Reiter, David E. Andersen
2013, PLoS ONE (8)
Quantifying spatial patterns of bird nests and nest fate provides insights into processes influencing a species’ distribution. At Cape Churchill, Manitoba, Canada, recent declines in breeding Eastern Prairie Population Canada geese (Branta canadensis interior) has coincided with increasing populations of nesting lesser snow geese (Chen caerulescens caerulescens) and Ross’s geese...
Case study Middle Rio Grande Basin, New Mexico, USA
Niel Plummer, W. Sanford
2013, Book chapter, Isotope Methods for Dating Old Groundwater
Chemical and isotopic patterns in groundwater can record characteristics of water sources, flow directions, and groundwater-age information. This hydrochemical information can be useful in refining conceptualization of groundwater flow, in calibration of numerical models of groundwater flow, and in estimation of paleo and modern recharge rates. This case...
Contaminants assessment in the coral reefs of Virgin Islands National Park and Virgin Islands Coral Reef National Monument
Timothy A. Bargar, Virginia H. Garrison, David A. Alvarez, Kathy Echols
2013, Marine Pollution Bulletin (70) 281-288
Coral, fish, plankton, and detritus samples were collected from coral reefs in Virgin Islands National Park (VIIS) and Virgin Islands Coral Reef National Monument (VICR) to assess existing contamination levels. Passive water sampling using polar organic chemical integrative samplers (POCIS) and semi-permeable membrane devices found a few emerging pollutants of...
Water resources of Plaquemines Parish, Louisiana
Larry B. Prakken
2013, Fact Sheet 2013-3031
In 2010, about 85.1 million gallons per day (Mgal/d) of water were withdrawn in Plaquemines Parish, Louisiana. Surface-water sources accounted for almost all withdrawals; groundwater sources accounted for only 0.04 Mgal/d. Industrial use accounted for about 92 percent of the total water withdrawn. Other categories of use included public supply,...
Water resources of St. Bernard Parish, Louisiana
Larry B. Prakken
2013, Fact Sheet 2013-3030
In 2010, about 261 million gallons per day (Mgal/d) of water were withdrawn in St. Bernard Parish, Louisiana, almost entirely from surface-water sources. Industrial use accounted for about 97 percent (253 Mgal/d) of the total water withdrawn. Other categories of use included public supply, rural domestic, and livestock. Water-use data...
Water resources of Natchitoches Parish, Louisiana
Robert B. Fendick Jr., Larry B. Prakken, Jason M. Griffith
2013, Fact Sheet 2013-3012
In 2005, about 33.8 million gallons per day (Mgal/d) was withdrawn from water sources in Natchitoches Parish, Louisiana. Surface water sources accounted for about 86 percent (29.2 Mgal/d) of all withdrawals whereas groundwater sources accounted for about 14 percent (4.62 Mgal/d). Withdrawals for industrial use accounted for about 42 percent...
Sediment accretion rates and sediment composition in Prairie Pothole wetlands under varying land use practices, Montana, United States
T.M. Preston, R.S. Sojda, R.A. Gleason
2013, Journal of Soil and Water Conservation (68) 199-211
Increased sedimentation and nutrient cycle changes in Prairie Pothole Region wetlands associated with agriculture threaten the permanence and ecological functionality of these important resources. To determine the effects of land use on sedimentation and nutrient cycling, soil cores were analyzed for cesium-137 (137Cs), lead-210 (210Pb), and potassium-40 (40K) activities; textural...
A domain decomposition approach to implementing fault slip in finite-element models of quasi-static and dynamic crustal deformation
Brad T. Aagaard, M.G. Knepley, C.A. Williams
2013, Journal of Geophysical Research B: Solid Earth (118) 3059-3079
We employ a domain decomposition approach with Lagrange multipliers to implement fault slip in a finite-element code, PyLith, for use in both quasi-static and dynamic crustal deformation applications. This integrated approach to solving both quasi-static and dynamic simulations leverages common finite-element data structures and implementations of various boundary conditions, discretization...
Temporal variation and scale in movement-based resource selection functions
M.B. Hooten, E.M. Hanks, D.S. Johnson, M.W. Alldredge
2013, Statistical Methodology (17) 82-98
A common population characteristic of interest in animal ecology studies pertains to the selection of resources. That is, given the resources available to animals, what do they ultimately choose to use? A variety of statistical approaches have been employed to examine this question and each has advantages and disadvantages with...