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Page 4138, results 103426 - 103450

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Sand boils without earthquakes
T.L. Holzer, M. M. Clark
1993, Geology (21) 873-876
Sedimentary deformation caused by liquefaction has become a popular means for inferring prehistoric strong earthquakes. In this report, we describe a new mechanism for generating such features in the absence of earthquakes. Sand boils and a 180-m-long sand dike formed in Fremont Valley,...
Mercury, arsenic, antimony, and selenium contents of sediment from the Kuskokwim River, Bethel, Alaska, USA
H. E. Belkin, H.M. Sparck
1993, Environmental Geology (22) 106-110
The Kuskokwim River at Bethel, Alaska, drains a major mercury-antimony metallogenic province in its upper reaches and tributaries. Bethel (population 4000) is situated on the Kuskokwim floodplain and also draws its water supply from wells located in river-deposited sediment. A boring through overbank and floodplain sediment has provided material to...
Effects of climate change on drought risks in the Apalachicola, Chattahoochee, and Flint River basin
Gary D. Tasker
1993, Conference Paper, Proceedings of the Symposium on Engineering Hydrology
Possible effects of climate change on the Apalachicola-Chattahoochee-Flint (ACF) River basin is simulated with a computer model. Model inputs are monthly temperature and precipitation that simulate several possible climate change scenarios. Preliminary results for climate scenarios based on output for three popular general circulation models indicate that lower flows will...
Pharmacokinetics, tissue distribution, and metabolism of nitrofurantoin in the channel catfish (Ictalurus punctatus)
Guy R. Stehly, S. M. Plakas
1993, Aquaculture (113) 1-10
The pharmacokinetics, tissue distribution, and metabolism of the drug nitrofurantoin were examined in the channel catfish (Ictalurus punctatus) after intravascular or oral dosing. Mean plasma concentrations of nitrofurantoin after intravascular administration at 1 and 10 mg kg−1 of body weight were best fit to two- and three-compartment pharmacokinetic models, respectively. Nitrofurantoin...
Application of borehole geophysics in defining the wellhead protection area for a fractured crystalline bedrock aquifer
J.H. Vernon, F.L. Paillet, W.H. Pedler, W.J. Griswold
1993, Log Analyst (34) 41-57
Wellbore geophysical techniques were used to characterize fractures and flow in a bedrock aquifer at a site near Blackwater Brook in Dover, New Hampshire. The primary focus ofthis study was the development of a model to assist in evaluating the area surrounding a planned water supply well where contaminants introduced...
Evaluation of subsurface exploration, sampling, and water-quality-analysis methods at an abandoned wood-preserving plant site at Jackson, Tennessee
W. S. Parks, J. K. Carmichael, J. E. Mirecki
1993, Water-Resources Investigations Report 93-4108
Direct Push Technology (DPT) and a modified-auger method of sampling were used at an abandoned wood-preserving plant site at Jackson, Tennessee, to collect lithologic data and ground-water samples in an area known to be affected by a subsurface creosote plume. The groundwater samples were analyzed using (1) gas chromatography with...
Cytonuclear genetic architecture in mosquitofish populations and the possible roles of introgressive hybridization
Kim T. Scribner, John C. Avise
1993, Molecular Ecology (2) 139-149
Spatial genetic structure in populations of mosquitofish (Gambusia) sampled throughout the south-eastern United States was characterized using mitochondrial (mt) DNA and allozyme markers. Both sets of data revealed a pronounced genetic discontinuity (along a broad path extending from south-eastern Mississippi to north-eastern Georgia) that corresponds to a recently recognized distinction...
Differentiation of bacterial feeding nematodes in soil ecological studies by means of arbitrarily primed PCR
Esther Van Der Knaap, Russell J. Rodriguez, Diana W. Freckman
1993, Soil Biology and Biochemistry (25) 1141-1151
Arbitrarily-primed polymerase chain reaction (ap-PCR) was used to differentiate closely related bacterial-feeding nematodes of the genera: Caenorhabditis, Acrobeloides, Cephalobus and Zeldia. Average percentage similarity of bands generated by ap-PCR with seven different primers between 14 isolates of Caenorhabditis elegans was ⪢ 90%, whereas between C. elegans, C. briggsae and C....
Identification of a whitefly species by genomic and behavioral studies
T.M. Perring, A.D. Cooper, R. J. Rodriguez, C.A. Farrar, T.S. Bellows Jr.
1993, Science (259) 74-77
An introduced whitefly species, responsible for over a half billion dollars in damage to U.S. agricultural production in 1991, is morphologically indistinguishable from Bemisia tabaci (Gennadius). However, with the use of polymerase chain reaction-based DNA differentiation tests, allozymic frequency analyses, crossing experiments, and mating behavior studies, the introduced whitefly is...
Hybrid zone dynamics are influenced by genotype-specific variation in life-history traits: Experimental evidence from hybridizing Gambusia species
Kim T. Scribner
1993, Evolution (47) 632-646
Results from two experiments are presented that contrast differences in life-history traits and population dynamics between two species of live bearing fishes (Gambusia affinis and G. holbrooki) that hybridize across portions of the southeastern United States. Progeny from parental holbrooki and holbrooki-affinis F1 crosses exhibited larger lengths at birth, at...
Determination of dissolved-phase pesticides in surface water from the Yakima River basin, Washington, using the Goulden large-sample extractor and gas chromatography/mass spectrometer
Gregory D. Foster, Paul M. Gates, William T. Foreman, Stuart W. McKenzie, Frank A. Rinella
1993, Environmental Science & Technology (27) 1911-1917
Concentrations of pesticides in the dissolved phase of surface water samples from the Yakima River basin, WA, were determined using preconcentration in the Goulden large-sample extractor (GLSE) and gas chromatography/mass spectrometry (GC/MS) analysis. Sample volumes ranging from 10 to 120 L were processed with the GLSE, and the results from...
Diatoms
J.A. Barron
1993, Book chapter, Fossil prokaryotes and protists
No abstract available ...
Great Basin NP and USGS cooperate on a geologic mapping program
Janet L. Brown, Vidal Davila Jr.
1993, Park Science (13) 6-7
The GRBA draft General Management Plan proposes development in several locations in Kious Spring and Lehman Caves 1:24,000 topographic quadrangles, and these proposed developments need geologic evaluation before construction. Brown will act as project manager to coordinate the IA with time frames, budget constraints, and the timely preparation of required...
Evidence for Holocene stability of steep slopes, northern Peruvian Andes, based on soils and radiocarbon dates
D. C. Miller, P. W. Birkeland, D. T. Rodbell
1993, Catena (20) 1-12
Radiocarbon dating and soil relationships indicate that landscapes in highaltitude glaciated valleys of the northern Peruvian Andes have been remarkably stable during the Holocene. Radiocarbon dates show that deglaciation was underway by 12 ka, and that slopes and alluvial fans at the bases of slopes were essentially stabilized by at...