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Page 22, results 526 - 550

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Publication Extents

Not all publications have extents, not all extents are completely accurate
Wolf-bison interactions in Yellowstone National Park
Douglas W. Smith, L. David Mech, Mary Meagher, Wendy E. Clark, Rosemary Jaffe, Michael K. Phillips, John A. Mack
2000, Journal of Mammalogy (81) 1128-1135
We studied interactions of reintroduced wolves (Canis lupus) with bison (Bison bison) in Yellowstone National Park. Only 2 of 41 wolves in this study had been exposed to bison before their translocation. Wolves were more successful killing elk (Cervus elaphus) than bison, and elk were more abundant than bison, so...
The state and future of Mars polar science and exploration
S.M. Clifford, D. Crisp, D.A. Fisher, Kenneth E. Herkenhoff, S.E. Smrekar, P.C. Thomas, D. D. Wynn-Williams, R.W. Zurek, J.R. Barnes, B.G. Bills, E.W. Blake, W. M. Calvin, J.M. Cameron, M. H. Carr, P. R. Christensen, B. C. Clark, G.D. Clow, J.A. Cutts, D. Dahl-Jensen, W.B. Durham, F. P. Fanale, J.D. Farmer, F. Forget, K. Gotto-Azuma, R. Grard, R.M. Haberle, W. Harrison, R. Harvey, A.D. Howard, A.P. Ingersoll, P.B. James, J.S. Kargel, H. H. Kieffer, J. Larsen, K. Lepper, M. C. Malin, D. J. McCleese, B. Murray, J.F. Nye, D. A. Paige, S.R. Platt, J.J. Plaut, N. Reeh, J.W. Rice, D.E. Smith, C. R. Stoker, K. L. Tanaka, E. Mosley-Thompson, T. Thorsteinsson, S.E. Wood, A. Zent, M.T. Zuber, H.J. Zwally
2000, Icarus (144) 210-242
As the planet's principal cold traps, the martian polar regions have accumulated extensive mantles of ice and dust that cover individual areas of ∼106 km2 and total as much as 3–4 km thick. From the scarcity of superposed craters on their surface, these layered deposits are thought to be comparatively young—preserving a...
Addendum to `numerical modeling of an enhanced very early time electromagnetic (VETEM) prototype system'
T.J. Cui, W.C. Chew, A.A. Aydiner, D.L. Wright, D.V. Smith, J.D. Abraham
2000, IEEE Antennas and Propagation Magazine (42) 54-57
Two numerical models to simulate an enhanced very early time electromagnetic (VETEM) prototype system that is used for buried-object detection and environmental problems are presented. In the first model, the transmitting and receiving loop antennas accurately analyzed using the method of moments (MoM), and then conjugate gradient (CG) methods with...
Environmental geochemistry at the global scale
J. Plant, D. Smith, B. Smith, L. Williams
2000, Journal of the Geological Society (157) 837-849
Land degradation and pollution caused by population pressure and economic development pose a threat to the sustainability of the Earth's surface, especially in tropical regions where a long history of chemical weathering has made the surface environment particularly fragile. Systematic baseline geochemical data provide a means of monitoring the state...
Influence of temperature and substrate on infection rate, triactinomyxon production, and release duration from eastern tubifex worms infected with Myxobolus cerebralis
Thomas Waldrop, Vicki Blazer, David Smith, Bane Schill, Christine Densmore
B. Schill, T. Waldrop, V. Blazer, editor(s)
1999, Book, 5th Annual Whirling Disease Symposium: Research and Management Perspectives
Salmonid whirling disease is caused by Myxobolus cerebralis, a metazoan parasite with a two host life cycle involving salmonid fish a an aquatic oligochaete, Tubifex tubifex (Wolf, Markiw and Hiltunen, 1986). Whirling disease has been reported in 22 U.S. states with the greatest losses occurring in the salmonid fisheries...
Preliminary effects of water hardness on triactinomyxon production and development from eastern tubifex worms infected with Myxobolus cerebralis
Thomas B. Waldrop, Christine Densmore, Vicki Blazer, Dave Smith, Bane Schill
B. Schill, T. Waldrop, V. Blazer, editor(s)
1999, Book, 5th Annual Whirling Disease Symposium: Research and Management Perspectives
Whirling disease is caused by Myxobolus cerebralis and requires an intermediate oligochaete host identified as Tubifex tubifex (Wolf, Markiw, and Hiltunen, 1986). M. cerebralis spores ingested by the tubifex worms develop into triactinomyxons (tams) that are eventually released into the water column to infect salmonid fish. There may...
Petrology and geochemistry of late-stage intrusions of the A-type, mid-Proterozoic Pikes Peak batholith (Central Colorado, USA): Implications for petrogenetic models
D. R. Smith, J. Noblett, R. A. Wobus, D. Unruh, J. Douglass, R. Beane, C. Davis, S. Goldman, G. Kay, B. Gustavson, B. Saltoun, J. Stewart
1999, Precambrian Research (98) 271-305
The ~1.08 Ga anorogenic, A-type Pikes Peak batholith (Front Range, central Colorado) is dominated by coarse-grained, biotite ?? amphibole syenogranites and minor monzogranites, collectively referred to as Pikes Peak granite (PPG). The batholith is also host to numerous small, late-stage plutons that have been subdivided into two groups (e.g. Wobus,...
The effects of crude oil and remediation burning on three clones of smooth cordgrass (Spartina alterniflora loisel.)
D.L. Smith, C.E. Proffitt
1999, Estuaries (22) 616-623
Burning has been employed as an oil spill remediation technique in coastal marshes, even though the combined and interactive effects of oil and burning on vegetation are poorly understood. Variation among clones of perennial marsh grasses in response to these perturbations is not known. We performed a greenhouse experiment designed...
Limits of retrospective power analysis
Patrick D. Gerard, David R. Smith, Govinda Weerakkody
1998, Journal of Wildlife Management (62) 801-807
Power analysis after study completion has been suggested to interpret study results. We present 3 methods of estimating power and discuss their limitations. We use simulation studies to show that estimated power can be biased, extremely variable, and severely bounded. We endorse the practice of computing power to detect a...
Electrogeochemical sampling with NEOCHIM - results of tests over buried gold deposits
R. W. Leinz, D.B. Hoover, D.L. Fey, D. B. Smith, T. Patterson
1998, Journal of Geochemical Exploration (61) 57-86
Electrogeochemical extraction methods are based on the migration of ions in an electric field. Ions present in soil moisture are transported by an applied current into fluids contained in special electrodes placed on the soil. The fluids are then collected and analyzed. Extractions are governed by Faraday's and Ohm's laws...
Impact of zebra and quagga mussels (Dreissena spp.) on freshwater unionids (Bivalvia: Unionidae) in the Detroit River of the Great Lakes
D. W. Schloesser, W. P. Kovalak, G. D. Longton, K. L. Ohnesorg, R. D. Smithee
1998, American Midland Naturalist (140) 299-313
To assess the impact of zebra and quagga mussel (Dreissena spp.) infestation on unionids, unionids (Bivalvia: Unionidae) were sampled in the Detroit River in 1982–1983, before mussels invaded the river, and in 1992 and 1994, after mussels invaded the river. Live unionids at four stations along the southeastern shore accounted for...
Results from the Mars global surveyor thermal emission spectrometer
P. R. Christensen, D.L. Anderson, S.C. Chase, R.T. Clancy, R. N. Clark, B.J. Conrath, H. H. Kieffer, R.O. Kuzmin, M. C. Malin, J.C. Pearl, T. L. Roush, M. D. Smith
1998, Science (279) 1692-1696
The Thermal Emission Spectrometer spectra of low albedo surface materials suggests that a four to one mixture of pyroxene to plagioclase, together with about a 35 percent dust component provides the best fit to the spectrum. Qualitative upper limits can be placed on the concentration of carbonates (<10 percent), olivine...