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179302 results.

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Page 7171, results 179251 - 179275

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Predicting species distributions: unifying model selection and scale optimization for multi-scale occupancy models
Bryan S. Stevens, Courtney J. Conway
None, Ecosphere (10)
Geographic distributions are a basic component of a species’ ecology, and predicting distributions is a fundamental task of conservation and resource management. Reliable prediction depends on identification of appropriate scales of effect for environmental data, and scale-optimization techniques are thus desirable to identify optimal scales for predictor variables. Recent statistical...
Detecting sulfamethoxazole and carbamazepine in groundwater: Is ELISA a reliable screening tool?
Aliesha L. Krall, Sarah M. Elliott, Melinda L. Erickson, Byron A. Adams
None, Environmental Pollution (234) 420-428
In recent years, numerous studies have reported the prevalence of organic micropollutants in natural waters. There is an increasing interest in assessing the occurrence and transport of these contaminants in groundwater because a large number of people in the United States rely on groundwater for their drinking water. However, commonly used mass-spectrometry-based...
Characterizing the interface between wild ducks and poultry to evaluate the potential of transmission of avian pathogens
Julien Cappelle, Nicolas Gaidet, S. A. Iverson, John Y. Takekawa, Scott H. Newman, Bouba Fofana, Marius Gilbert
None, International Journal of Health Geographics (10)
BackgroundCharacterizing the interface between wild and domestic animal populations is increasingly recognized as essential in the context of emerging infectious diseases (EIDs) that are transmitted by wildlife. More specifically, the spatial and temporal distribution of contact rates between wild and domestic hosts is a key parameter for modeling...
Using indirect methods to constrain symbiotic nitrogen fixation rates: A case study from an Amazonian rain forest
C.C. Cleveland, B.Z. Houlton , C Neill, Sasha C. Reed, Y Wang, A.R. Townsend
None, Biogeochemistry (99) 1-13
Human activities have profoundly altered the global nitrogen (N) cycle. Increases in anthropogenic N have had multiple effects on the atmosphere, on terrestrial, freshwater and marine ecosystems, and even on human health. Unfortunately, methodological limitations challenge our ability to directly measure natural N inputs via biological N fixation (BNF)-the largest natural source...
Simulation of the long term radiometric responses of the Terra MODIS and EO-1 ALI using Hyperion spectral responses over Railroad Valley Playa in Nevada (RVPN)
Taeyoung Choi, Xiaoxiong Xiong, Amit Angal, Gyanesh Chander
None, Conference Paper, Proceedings of SPIE 7862, Earth observing missions and sensors: Development, implementation, and characterization
The Earth Observing-1 (EO-1) Hyperion instrument provides 220 spectral bands with wavelengths between 400 and 2500 nm at 30 m spatial resolution, which covers a 7.5 km by 100 km area on the ground. The EO-1 spacecraft has another multispectral sensor called the Advanced Land Imager (ALI), which has 10...
Silurian-Devonian age and tectonic setting of the Connecticut Valley-Gaspé trough of Vermont using U-Pb SHRIMP analyses of detrital zircons
C. K. McWilliams, Gregory J. Walsh, Robert P. Wintsch
None, American Journal of Science (310) 325-363
U-Pb SHRIMP ages of detrital zircons from metasedimentary rocks of the Connecticut Valley-Gaspe' trough in Vermont corroborate a Silurian-Devonian age of deposition for these strata and constrain their provenances. Ages of randomly selected detrital zircons obtained from quartzites within the Waits River and Gile Mountain Formations range from Archean to...
New approaches to stability analysis of steep coastal bluffs
Brian D. Collins, Nicholas Sitar
None, Conference Paper, Proceedings of geocongress 2008
We present a discussion on the limitations and needed improvements for existing slope stability analysis methods to accurately model steep coastal bluff failures resulting from both direct wave action at the toe in weakly cemented sands and precipitation-induced seepage failures in moderately cemented sands. Using a case-study detailing over 5...
Modeling of wave driven circulation and water quality in nearshore environments
Craig Jones, Stephen J. Angster
None, Conference Paper, Proceedings of the 2008 world environmental and water resources congress
In order to investigate the effects of nearshore discharges of water quality degrading substances and bacteria in coastal environments, models capable of predicting nearshore circulation due to local wave and tide conditions are required. One of the larger challenges to nearshore coastal modeling is accurately reproducing nearshore circulation due to...
Cross-borehole flow tests and insights into hydraulic connections in fractured mudstone and sandstone
John H. Williams, Pierre Lacombe, Carole D. Johnson, Frederick L. Paillet
None, Conference Paper, Symposium on the Application of Geophysics to Engineering and Environmental Problems
Cross-borehole flow tests provided insights into hydraulic connections in fractured and dipping mudstone and sandstone that were consistent with the lithostratigraphic and structural framework of a VOCcontaminated bedrock research site in west-central New Jersey. Two cross-borehole flow tests were completed. Each test involved measurement and analysis of transient flow in...
Characterizing the two-dimensional thermal conductivity distribution in a sand and gravel aquifer
Jeff M. Markle, Robert A. Schincariol, J. H. Sass, John W. Molson
None, Soil Science Society of America Journal (70) 1281-1294
Both hydrologic and thermal transport properties play a significant role in the movement of heat through permeable sedimentary material; however, the thermal conductivity is rarely characterized in detailed spatial resolution. As part of a study of the movement of thermal plumes through a sand and gravel aquifer, we have constructed...
Scouting craton’s edge in Paleo-Pacific Gondwana
Carol A. Finn, John W. Goodge, Detlef Damaske, C. Mark Fanning
Dieter Karl Fütterer, Georg Kleinschmidt, Hubert Miller, Franz Tessensohn, editor(s)
None, Book chapter, Antarctica: Contributions to global earth sciences
The geology of the ice-covered interior of the East Antarctic shield is completely unknown; inferences about its composition and history are based on extrapolating scant outcrops from the coast inland. Although the shield is clearly composite in nature, a large part of its interior has been represented by a single...
Remnant damage from the 1906 San Francisco earthquake
John Boatwright
Carol S. Prentice, Judith G. Scotchmoor, Eldridge M. Moores, Jon P. Kiland, editor(s)
None, Book chapter, 1906 San Francisco earthquake centennial field guides: Field trips associated with the 100th Anniversary Conference, 18–23 April 2006, San Francisco, California
This field trip consists of two stops at locations where it is possible to see damage from the 1906 earthquake and to gauge the intensity of the ground shaking that caused the damage. The first stop is at a cemetery in Colma, where the damage to monuments and headstones was...
Oligocene and earliest Miocene diatom biostratigraphy of ODP leg 199 site 1220, equatorial Pacific
John A. Barron, Elisabeth Fourtanier, S. M. Bohaty
None, Proceedings of the Ocean Drilling Program: Scientific Results (199)
Completion of studies on material collected during Ocean Drilling Program Leg 199 at Site 1220 in the equatorial Pacific allows calibration of the ranges of >35 stratigraphically important diatoms to paleomagnetic stratigraphy for the Oligocene and earliest Miocene (~33.5–21.5 Ma). The taxonomy of these taxa is reviewed, and age estimates...
Integrated geophysical characterization of the Winthrop Landfill Southern Flow Path, Winthrop, Maine
Cian B. Dawson, John W. Lane Jr., Eric A. White, Marcel Belaval
None, Conference Paper, Proceedings: Symposium on the application of geophysics to engineering and environmental problems
The U.S. Geological Survey (USGS), in cooperation with United Technologies Corporation, used an integrated suite of borehole, surface, and water-borne geophysical methods near the site of the former Winthrop Landfill, Winthrop, Maine, to investigate the hydrogeology controlling the transport of leachate from the landfill to nearby Annabessacook Lake. During the...
Perspectives on the diagnosis, epizootiology, and control of the 1973 duck plague epizootic in wild waterfowl at Lake Andes, South Dakota
Gary L. Pearson, Delmar R. Cassidy
None, Journal of Wildlife Diseases (33 ) 681-705
An epizootic of duck plague occurred in early 1973 in a population of 163,500 wild waterfowl, primarily mallards (Anas platyrhynchos), wintering on Lake Andes and the nearby Missouri River in southeastern South Dakota (USA). The diagnosis was based on pathologic lesions and confirmed by virus isolation. Control measures included quarantine, attempts...
Exsolved magmatic fluid and its role in the formation of comb-layered quartz at the Cretaceous Logtung W-Mo deposit, Yukon Territory, Canada
Jacob B. Lowenstern, W. David Sinclair
None, Book chapter, The Third Hutton symposium on the origin of granites and related rocks
Comb-layered quartz is a type of unidirectional solidification texture found at the roofs of shallow silicic intrusions that are often associated spatially with Mo and W mineralisation. The texture consists of multiple layers of euhedral, prismatic quartz crystals (Type I) that have grown on subplanar aplite substrates. The layers are...
Geodetic monitoring of the southern San Andreas Fault, California, 1980-1991
James C. Savage, Michael Lisowski
None, Journal of Geophysical Research (100) 8185-8192
Five geodetic arrays (10 to 40 km aperture) located along the San Andreas fault have been surveyed frequently (several times in most years) over the 1980–1991 interval to detect possible fluctuations in the deformation rate. In each survey of an array the distances between the same four to seven pairs...