Skip to main content
U.S. flag

An official website of the United States government

Dot gov

Official websites use .gov
A .gov website belongs to an official government organization in the United States.

Https

Secure .gov websites use HTTPS
A lock ( ) or https:// means you’ve safely connected to the .gov website. Share sensitive information only on official, secure websites.

Search Results

165658 results.

Alternate formats: RIS file of the first 3000 search results  |  Download all results as CSV | TSV | Excel  |  RSS feed based on this search  |  JSON version of this page of results

Page 1414, results 35326 - 35350

Show results on a map

Publication Extents

Not all publications have extents, not all extents are completely accurate
Seasonal circulation over the Catalan inner-shelf (northwest Mediterranean Sea)
Manel Grifoll, Alfredo L. Aretxabaleta, Josep L. Pelegri, Manuel Espino, John C. Warner, Agustin Sanchez-Arcilla
2013, Journal of Geophysical Research C: Oceans (118) 5844-5857
This study characterizes the seasonal cycle of the Catalan inner-shelf circulation using observations and complementary numerical results. The relation between seasonal circulation and forcing mechanisms is explored through the depth-averaged momentum balance, for the period between May 2010 and April 2011, when velocity observations were partially available. The monthly-mean along-shelf...
Alternative ways of using field-based estimates to calibrate ecosystem models and their implications for carbon cycle studies
Yujie He, Qianlai Zhuang, David McGuire, Yaling Liu, Min Chen
2013, Journal of Geophysical Research: Biogeosciences (118) 983-993
Model-data fusion is a process in which field observations are used to constrain model parameters. How observations are used to constrain parameters has a direct impact on the carbon cycle dynamics simulated by ecosystem models. In this study, we present an evaluation of several options for the use of observations...
Vs30 and spectral response from collocated shallow, active- and passive-source Vs data at 27 sites in Puerto Rico
Jack K. Odum, William J. Stephenson, Robert A. Williams, Christa von Hillebrandt-Andrade
2013, Bulletin of the Seismological Society of America (103) 2709-2728
Shear‐wave velocity (VS) and time‐averaged shear‐wave velocity to 30 m depth (VS30) are the key parameters used in seismic site response modeling and earthquake engineering design. Where VS data are limited, available data are often used to develop and refine map‐based proxy models of VS30 for predicting ground‐motion intensities. In...
Temporal, spatial, and body size effects on growth rates of loggerhead sea turtles (Caretta caretta) in the Northwest Atlantic
Karen A. Bjorndal, Barbara A. Schroeder, Allen M. Foley, Blair E. Witherington, Michael Bresette, David Clark, Richard M. Herren, Michael D. Arendt, Jeffrey R. Schmid, Anne B. Meylan, Peter A. Meylan, Jane A. Provancha, Kristen M. Hart, Margaret M. Lamont, Raymond R. Carthy, Alan B. Bolten
2013, Marine Biology (160) 2711-2721
In response to a call from the US National Research Council for research programs to combine their data to improve sea turtle population assessments, we analyzed somatic growth data for Northwest Atlantic (NWA) loggerhead sea turtles (Caretta caretta) from 10 research programs. We assessed growth dynamics over wide ranges of...
Seasonal persistence of marine-derived nutrients in south-central Alaskan salmon streams
Daniel J. Rinella, Mark S. Wipfi, Coowe M. Walker, Craig A. Stricker, Ron A. Heintz
2013, Ecosphere (4)
Spawning salmon deliver annual pulses of marine-derived nutrients (MDN) to riverine ecosystems around the Pacific Rim, leading to increased growth and condition in aquatic and riparian biota. The influence of pulsed resources may last for extended periods of time when recipient food webs have effective storage mechanisms, yet few studies...
Analysis of Neogene deformation between Beaver, Utah and Barstow, California: Suggestions for altering the extensional paradigm
R. Ernest Anderson, Sue Beard, Edward A. Mankinen, John W. Hillhouse
2013, Geological Society of America Special Papers (499) 1-67
For more than two decades, the paradigm of large-magnitude (~250 km), northwest-directed (~N70°W) Neogene extensional lengthening between the Colorado Plateau and Sierra Nevada at the approximate latitude of Las Vegas has remained largely unchallenged, as has the notion that the strain integrates with coeval strains in adjacent regions and with...
Characterizing and estimating noise in InSAR and InSAR time series with MODIS
William D. Barnhart, Rowena B. Lohman
2013, Geochemistry, Geophysics, Geosystems (14) 4121-4132
InSAR time series analysis is increasingly used to image subcentimeter displacement rates of the ground surface. The precision of InSAR observations is often affected by several noise sources, including spatially correlated noise from the turbulent atmosphere. Under ideal scenarios, InSAR time series techniques can substantially mitigate these effects; however, in...
Integrating complexity into data-driven multi-hazard supply chain network strategies
Suzanna K. Long, Thomas G. Shoberg, Varun Ramachandran, Steven M. Corns, Hector J. Carlo
2013, Book, Proceedings of the ASPRS\CaGIS 2013 Specialty Conference
Major strategies in the wake of a large-scale disaster have focused on short-term emergency response solutions. Few consider medium-to-long-term restoration strategies that reconnect urban areas to the national supply chain networks (SCN) and their supporting infrastructure. To re-establish this connectivity, the relationships within the SCN must be defined and formulated...
Links between climate change, water-table depth, and water chemistry in a mineralized mountain watershed
Andrew H. Manning, Philip L. Verplanck, Jonathan S. Caine, Andrew S. Todd
2013, Applied Geochemistry (37) 64-78
Recent studies suggest that climate change is causing rising solute concentrations in mountain lakes and streams. These changes may be more pronounced in mineralized watersheds due to the sensitivity of sulfide weathering to changes in subsurface oxygen transport. Specific causal mechanisms linking climate change and accelerated weathering rates have been...
Usefulness of hemocytometer as a counting chamber in a computer assisted sperm analyzer (CASA)
A. Eljarah, J. Chandler, J.A. Jenkins, J. Chenevert, A. Alcanal
2013, Animal Reproduction (10) 708-711
Several methods are used to determine sperm cell concentration, such as the haemocytometer, spectrophotometer, electronic cell counter and computer-assisted semen analysers (CASA). The utility of CASA systems has been limited due to the lack of characterization of individual systems and the absence of standardization among laboratories. The aims of this...
The innate immune response may be important for surviving plague in wild Gunnison's prairie dogs
Joseph D. Busch, Roger Van Andel, Nathan E. Stone, Kacy R. Cobble, Roxanne Nottingham, Judy Lee, Michael VerSteeg, Jeff Corcoran, Jennifer Cordova, William E. Van Pelt, Megan M. Shuey, Jeffrey T. Foster, James M. Schupp, Stephen Beckstrom-Sternberg, James Beckstrom-Sternberg, Paul Keim, Susan Smith, Julia Rodriguez-Ramos, Judy L. Williamson, Tonie E. Rocke, David M. Wagner
2013, Journal of Wildlife Diseases (49) 920-931
Prairie dogs (Cynomys spp.) are highly susceptible to Yersinia pestis, with ≥99% mortality reported from multiple studies of plague epizootics. A colony of Gunnison's prairie dogs (Cynomys gunnisoni) in the Aubrey Valley (AV) of northern Arizona appears to have survived several regional epizootics of plague, whereas nearby colonies have been...
Multivariate analysis of ATR-FTIR spectra for assessment of oil shale organic geochemical properties
Kathryn E. Washburn, Justin E. Birdwell
2013, Organic Geochemistry (63) 1-7
In this study, attenuated total reflectance (ATR) Fourier transform infrared spectroscopy (FTIR) was coupled with partial least squares regression (PLSR) analysis to relate spectral data to parameters from total organic carbon (TOC) analysis and programmed pyrolysis to assess the feasibility of developing predictive models to estimate important organic geochemical parameters....
Retrospective analysis of bottlenose dolphin foraging: a legacy of anthropogenic ecosystem disturbance
Sam Rossman, Nélio B. Barros, Peggy H. Ostrom, Craig A. Stricker, Aleta A. Hohn, Hasand Gandhi, Randall S. Wells
2013, Marine Mammal Science (29) 705-718
We used stable isotope analysis to investigate the foraging ecology of coastal bottlenose dolphins (Tursiops truncatus) in relation to a series of anthropogenic disturbances. We first demonstrated that stable isotopes are a faithful indicator of habitat use by comparing muscle isotope values to behavioral foraging data from the same individuals....
A multilocus evaluation of ermine (Mustela erminea) across the Holarctic, testing hypotheses of Pleistocene diversification in response to climate change
Natalie G. Dawson, Andrew G. Hope, Sandra L. Talbot, Joseph A. Cook
2013, Journal of Biogeography (41) 464-475
Aim: We examined data for ermine (Mustela erminea) to test two sets of diversification hypotheses concerning the number and location of late Pleistocene refugia, the timing and mode of diversification, and the evolutionary influence of insularization. Location: Temperate and sub-Arctic Northern Hemisphere. Methods: We used up to two mitochondrial and four nuclear...
Social-ecological predictors of global invasions and extinctions
Aaron Lotz, Craig R. Allen
2013, Ecology and Society (18)
Most assessments of resilience have been focused on local conditions. Studies focused on the relationship between humanity and environmental degradation are rare, and are rarely comprehensive. We investigated multiple social-ecological factors for 100 countries around the globe in relation to the percentage of invasions and extinctions within each country. These...
Evaluation of potential gas clogging associated with managed aquifer recharge from a spreading basin, southwestern Utah, U.S.A.
Victor M. Heilweil, Thomas Marston
2013, Book chapter, Clogging issues associated with managed aquifer recharge methods
Sand Hollow Reservoir in southwestern Utah, USA, is operated for both surface-water storage and managed aquifer recharge via infiltration from surface basin spreading to the underlying Navajo Sandstone. The total volume of estimated recharge from 2002 through 2011 was 131 Mm3., resulting in groundwater levels rising as much as 40...
Prescribed-fire effects on an aquatic community of a southwest montane grassland system
Colleen A. Caldwell, Gerald Z. Jacobi, Michael C. Anderson, Robert R. Parmenter, Jeanine McGann, William R. Gould, Robert DuBey, M. Donna Jacobi
2013, North American Journal of Fisheries Management (33) 1049-1062
The use of prescription fire has long been recognized as a reliable management tool to suppress vegetative succession processes and to reduce fuel loading to prevent catastrophic wildfires, but very little attention has been paid to the effects on aquatic systems. A late-fall prescribed burn was implemented to characterize effects...
Comparing two fish sampling standards over time: largely congruent results but with caveats
Daniel L. Yule, Lori M. Evrard, Sebastien Cachera, Michel Colon, Jean Guillard
2013, Freshwater Biology (58) 2074-2088
1. We sampled Lake Bourget (surface area = 44 km2) using CEN standard gillnet and provisional standard acoustic survey methods over 3 years (2005, 2010 and 2011) as the fish community responded to re-oligotrophication. A total of 16 species were caught in benthic gillnets and three species in pelagic...
Development of a reproducible method for determining quantity of water and its configuration in a marsh landscape
Glenn M. Suir, D. Elaine Evers, Gregory D. Steyer, Charles E. Sasser
2013, Journal of Coastal Research 110-117
Coastal Louisiana is a dynamic and ever-changing landscape. From 1956 to 2010, over 3,734 km2 of Louisiana's coastal wetlands have been lost due to a combination of natural and human-induced activities. The resulting landscape constitutes a mosaic of conditions from highly deteriorated to relatively stable with intact landmasses. Understanding how...
Experimental reintroduction reveals novel life-history variation in Laysan Ducks (Anas laysanensis)
Jeffrey R. Walters, Michelle H. Reynolds
2013, The Auk (130) 573-579
Subfossil remains indicate that the Laysan Duck (Anas laysanensis) formerly occurred throughout the Hawaiian archipelago, but for more than 150 years it has been confined to a single, small atoll in the northwestern chain, Laysan Island. In 2004–2005, 42 ducks were reintroduced from Laysan to Midway Atoll, where they exhibited...
The biogeographic histories of Pinus edulis and Pinus monophylla over the last 50,000 years
Kenneth L. Cole, Jessica F. Fisher, Kirsten E. Ironside, Jim I. Mead, Peter Koehler
2013, Quaternary International (310) 96-110
Well-preserved pine needles found in fossil packrat middens document the biogeographic responses of pinyon pines to changing climates over the last 50,000 years. During the full glacial Wisconsinan (MIS2), Pinus monophylla (single-needle pinyon), Pinus edulis (Colorado pinyon), and P. edulis var. fallax (Arizona singleleaf pinyon) all grew along the southern portions of their current ranges. P. monophylla extended from the southern...
Tsunami flooding
Eric Geist, Henry Jones, Mark McBride, Randy Fedors
2013, Conference Paper, Proceedings of the Workshop on Probabilistic Flood Hazard Assessment (PFHA): Held at the U.S. Nuclear Regulatory Commission Headquarters, Rockville, MD, January 29_31, 2013 (NUREG/CP-0302)
Panel 5 focused on tsunami flooding with an emphasis on Probabilistic Tsunami Hazard Analysis (PTHA) as derived from its counterpart, Probabilistic Seismic Hazard Analysis (PSHA) that determines seismic ground-motion hazards. The Panel reviewed current practices in PTHA and determined the viability of extending the analysis to extreme design probabilities (i.e.,...
Creel survey sampling designs for estimating effort in short-duration Chinook salmon fisheries
Joshua L. McCormick, Michael C. Quist, Daniel J. Schill
2013, North American Journal of Fisheries Management (33) 977-993
Chinook Salmon Oncorhynchus tshawytscha sport fisheries in the Columbia River basin are commonly monitored using roving creel survey designs and require precise, unbiased catch estimates. The objective of this study was to examine the relative bias and precision of total catch estimates using various sampling designs to estimate angling effort...
An international network of magnetic observatories
Jeffrey J. Love, A. Chulliat
2013, Eos, Transactions, American Geophysical Union (94) 373-374
Since its formation in the late 1980s, the International Real-Time Magnetic Observatory Network (INTERMAGNET), a voluntary consortium of geophysical institutes from around the world, has promoted the operation of magnetic observatories according to modern standards [eg. Rasson, 2007]. INTERMAGNET institutes have cooperatively developed infrastructure for data exchange and management ads...
Spatial variability of "Did You Feel It?" intensity data: insights into sampling biases in historical earthquake intensity distributions
Susan E. Hough
2013, Bulletin of the Seismological Society of America (103) 2767-2781
Recent parallel development of improved quantitative methods to analyze intensity distributions for historical earthquakes and of web‐based systems for collecting intensity data for modern earthquakes provides an opportunity to reconsider not only important individual historical earthquakes but also the overall characterization of intensity distributions for historical events. The focus of...