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2003

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Focus Emu, February 4, 2003, Office Of Public Information Jan 2003

Focus Emu, February 4, 2003, Office Of Public Information

Focus EMU

No abstract provided.

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Focus Emu, August 12, 2003, Office Of Public Information Jan 2003

Focus Emu, August 12, 2003, Office Of Public Information

Focus EMU

No abstract provided.

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Focus Emu, February 28, 2003, Office Of Public Information Jan 2003

Focus Emu, February 28, 2003, Office Of Public Information

Focus EMU

No abstract provided.

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Recovering Species Of Conservation Concern-Are Populations Expendable?, May Ruckelshaus, Paul Mcelhany, Michael J. Ford Jan 2003

Recovering Species Of Conservation Concern-Are Populations Expendable?, May Ruckelshaus, Paul Mcelhany, Michael J. Ford

United States Department of Commerce: Staff Publications

Simply mentioning the notion of species expendability may seem reprehensible, but it is a question raised often when conservation biology meets conservation practice, as in this volume. In particular, when arguing for the value of biodiversity, biologists are faced with the challenge of examining the roles that particular species might play in community function and whether there are redundancies in the functions of certain species. Does every species need to be conserved for our ecosystems to function? The question of expendability also is important in conservation planning that occurs at the species level: does every population need to be saved …

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The Abundance Of Harbor Seals In The Gulf Of Alaska, Peter Boveng, John Bengtson, David Withrow, Jack Cesarone, Michael Simpkins, Kathryn Frost, John Burns Jan 2003

The Abundance Of Harbor Seals In The Gulf Of Alaska, Peter Boveng, John Bengtson, David Withrow, Jack Cesarone, Michael Simpkins, Kathryn Frost, John Burns

United States Department of Commerce: Staff Publications

The abundance of harbor seals (Phoca vitulina richardii) has declined in recent decades at several Alaska locations. The causes of these declines are unknown, but there is concern about the status of the populations, especially in the Gulf of Alaska. To assess the status of harbor seals in the Gulf of Alaska, we conducted aerial surveys of seals on their haul-out sites in August-September 1996. Many factors influence the propensity of seals to haul out, including tides, weather, time of day, and time of year. Because these “covariates” cannot simultaneously be controlled through survey design, we used a …

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Low Frequency Calls Of Bryde's Whales, Erin M. Oleson, Jay Barlow, Jonathan Gordon, Shannon Rankin, John A. Hildebrand Jan 2003

Low Frequency Calls Of Bryde's Whales, Erin M. Oleson, Jay Barlow, Jonathan Gordon, Shannon Rankin, John A. Hildebrand

United States Department of Commerce: Staff Publications

Despite significant effort, only two published reports describe Bryde's whale (Balaenoptera edeni) calls (Cummings et al. 1986, Edds et al. 1993). In both studies fundamental call frequencies were greater than 90 Hz, somewhat higher than the call frequencies attributed to other balaenopterids (Clark 1990, Edds-Walton 1997). Through opportunistic acoustic recordings, we obtained and analyzed numerous examples of Bryde's whale calls from three habitats: the Eastern Tropical Pacific (ETP), the southern Caribbean, and the northwest Pacific near the coast of Japan. In all but a single case, call frequencies of 60 Hz or less were observed.

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A Model Life Table For Bottlenose Dolphins (Tursiops Truncatus) From The Indian River Lagoon System, Florida, U.S.A., Megan K. Stolen, Jay Barlow Jan 2003

A Model Life Table For Bottlenose Dolphins (Tursiops Truncatus) From The Indian River Lagoon System, Florida, U.S.A., Megan K. Stolen, Jay Barlow

United States Department of Commerce: Staff Publications

Data gathered from 220 stranded bottlenose dolphins (Tzmiop tvuncatlls) in the Indian River Lagoon system, Florida, were used to derive a life table. Survivorship curves were fit to the data using Siler’s competing-risk model and a maximum likelihood approach. Population growth was estimated to be between r = 0.0 and 0.046 based on the observed numbers of stranded dolphins. Variance in survival rates was estimated using an individual-based, age-structured population projection model. We estimate that the overall annual mortality rate for this population was 9.8% per year. Sex-specific differences in survivorship were apparent with females outliving males. The …

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Trends In The Benthic Macroinvertebrate Community Of Saginaw Bay, Lake Huron, 1987 To 1996: Responses To Phosphorus Abatement And The Zebra Mussel, Dreissena Polymorpha, Thomas F. Nalepa, David L. Fanslow, Margaret B. Lansing, Gregory A. Lang Jan 2003

Trends In The Benthic Macroinvertebrate Community Of Saginaw Bay, Lake Huron, 1987 To 1996: Responses To Phosphorus Abatement And The Zebra Mussel, Dreissena Polymorpha, Thomas F. Nalepa, David L. Fanslow, Margaret B. Lansing, Gregory A. Lang

United States Department of Commerce: Staff Publications

Trends in benthic macroinvertebrate populations were examined in inner and outer Saginaw Bay, Lake Huron, from 1987 to 1996. These years represent the time period after phosphorus abatement, but immediately before (1987 to 1990) and after (1991 to 1996) colonization of the bay by the zebra mussel, Dreissena polymorpha. In 1987 to 1990, densities of the major macroinvertebrate groups in the inner and outer bay were not significantly different from, or were greater than, densities reported just prior to abatement efforts in the early 1970s. Oligochaete densities in the deepwater/silt region of the inner bay were trending downward between …

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Stream Bank Stability In Eastern Nebraska, Philip J. Soenksen, Mary J. Turner, Benjamin J. Dietsch, Andrew Simon Jan 2003

Stream Bank Stability In Eastern Nebraska, Philip J. Soenksen, Mary J. Turner, Benjamin J. Dietsch, Andrew Simon

United States Geological Survey: Publications

Dredged and straightened channels in eastern Nebraska have experienced degradation leading to channel widening by bank failure. Degradation has progressed headward and affected the drainage systems upstream from the modified reaches. This report describes a study that was undertaken to analyze bank stability at selected sites in eastern Nebraska and develop a simplified method for estimating the stability of banks at future study sites. Bank cross sections along straight reaches of channel and geotechnical data were collected at approximately 150 sites in 26 counties of eastern Nebraska. The sites were categorized into three groups based on mapped soil permeability. With …

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Streambed Adjustment And Channel Widening In Eastern Nebraska, David L. Rus, Benjamin J. Dietsch, Andrew Simon Jan 2003

Streambed Adjustment And Channel Widening In Eastern Nebraska, David L. Rus, Benjamin J. Dietsch, Andrew Simon

United States Geological Survey: Publications

In eastern Nebraska, stream straightening and dredging efforts since the 1890s have disturbed the natural equilibrium of stream channels and have led to streambed adjustment by degradation and subsequent channel widening. This report describes a study to evaluate the effect these disturbances have had on stream channels in eastern Nebraska.

Two sets of survey data were collected approximately 2 years apart during 1996–99 at 151 primary sites. Additionally, historical streambed-elevation data (dating back to the 1890s) were compiled from several sources for the primary sites and 45 supplemental sites, and relevant disturbances were identified for each of eight basin groupings. …

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Reconnaissance Of Acid Drainage Sources And Preliminary Evaluation Of Remedial Alternatives At The Copper Bluff Mine, Hoopa Valley Reservation, California, Charles N. Alpers, Michael P. Hunerlach, Scott N. Hamlin, Robert A. Zierenberg Jan 2003

Reconnaissance Of Acid Drainage Sources And Preliminary Evaluation Of Remedial Alternatives At The Copper Bluff Mine, Hoopa Valley Reservation, California, Charles N. Alpers, Michael P. Hunerlach, Scott N. Hamlin, Robert A. Zierenberg

United States Geological Survey: Publications

Acidic drainage from the inactive Copper Bluff mine cascades down a steep embankment into the Trinity River, on the Hoopa Valley Reservation in northern California. The Copper Bluff mine produced about 100,000 tons of sulfide-bearing copper-zinc-gold-silver ore during 1957–1962. This report summarizes the results of a water-resources investigation begun by the U.S. Geological Survey in 1994 with the overall objective of gathering sufficient geochemical, hydrologic, and geologic information so that a sound remediation strategy for the Copper Bluff mine could be selected and implemented by the Hoopa Valley Tribe. This study had the following specific objectives: (1) monitor the quality …

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Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft Jan 2003

Sediment-Water Interactions Affecting Dissolved-Mercury Distributions In Camp Far West Reservoir, California, James S. Kuwabara, Charles N. Alpers, Mark Marvin-Dipasquale, Brent R. Topping, James L. Carter, A. Robin Stewart, Steven V. Fend, Francis Parchaso, Gerald E. Moon, David P. Krabbenhoft

United States Geological Survey: Publications

Field and laboratory studies were conducted in April and November 2002 to provide the first direct measurements of the benthic flux of dissolved (0.2-micrometer filtered) mercury species (total and methylated forms) between the bottom sediment and water column at three sampling locations within Camp Far West Reservoir, California: one near the Bear River inlet to the reservoir, a second at a mid-reservoir site of comparable depth to the inlet site, and the third at the deepest position in the reservoir near the dam (herein referred to as the inlet, midreservoir and near-dam sites, respectively; Background, Fig. 1). Because of interest …

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Quantifying The Effects Of Small-Scale Heterogeneities On Flow And Transport In Undisturbed Cores From The Hanford Formation, M. N. Pace, M. A. Mayes, P. M. Jardine, T. L. Mehlhorn, John M. Zachara, B.N. Bjornstad Jan 2003

Quantifying The Effects Of Small-Scale Heterogeneities On Flow And Transport In Undisturbed Cores From The Hanford Formation, M. N. Pace, M. A. Mayes, P. M. Jardine, T. L. Mehlhorn, John M. Zachara, B.N. Bjornstad

United States Department of Energy: Publications

Accelerated migration of contaminants in the vadose zone has been observed beneath tank farms at the U.S. Department of Energy’s Hanford Reservation, Richland, WA. This paper focuses on quantifying hydrologic processes that control the fate and transport of contaminants in the unsaturated sediments beneath the Hanford tank farms. The experimental approach involved the use of field relevant, long-term unsaturated nonreactive transport experiments in undisturbed sediments from the Hanford Formation. Undisturbed sediment cores were collected from a laminated fine-grained sand unit within the Hanford Formation in both the vertical direction (flow cross bedding) and the horizontal direction (flow bedding parallel). Laboratory-scale …

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Deformation Of A Peridynamic Bar, S. A. Silling, M. Zimmermann, R. Abeyaratne Jan 2003

Deformation Of A Peridynamic Bar, S. A. Silling, M. Zimmermann, R. Abeyaratne

United States Department of Energy: Publications

The deformation of an infinite bar subjected to a self-equilibrated load distribution is investigated using the peridynamic formulation of elasticity theory. The peridynamic theory differs from the classical theory and other nonlocal theories in that it does not involve spatial derivatives of the displacement field. The bar problem is formulated as a linear Fredholm integral equation and solved using Fourier transform methods. The solution is shown to exhibit, in general, features that are not found in the classical result. Among these are decaying oscillations in the displacement field and progressively weakening discontinuities that propagate outside of the loading region. These …

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Heterogeneous Electron-Transfer Kinetics With Synchrotron 57fe Mossbauer Spectroscopy, J. E. Amonette, Ravi K. Kukkadapu, E. E. Alp, W. Sturhahn, T. S. Toellner Jan 2003

Heterogeneous Electron-Transfer Kinetics With Synchrotron 57fe Mossbauer Spectroscopy, J. E. Amonette, Ravi K. Kukkadapu, E. E. Alp, W. Sturhahn, T. S. Toellner

United States Department of Energy: Publications

In the first known kinetic application of the technique, synchrotron 57Fe-Mössbauer spectroscopy was used to follow the rate of heterogeneous electron transfer between aqueous reagents and a solid phase containing Fe. The solid, a synthetic 57Fe-enriched Fe (III)-bearing pyroaurite-like phase having terephthalate (TA) in the interlayer [Mg3Fe (OH)8(TA)0.5 • 2H2O], was reduced by Na2S2O4 and then reoxidized by K2Cr2O7 by means of a novel flow-through cell. Synchrotron Mössbauer spectra were collected in the time domain at 30-s intervals. Integration of the …

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Adaptive Harvest Management: 2003 Duck Hunting Season Jan 2003

Adaptive Harvest Management: 2003 Duck Hunting Season

United States Fish and Wildlife Service: Publications

The process of setting waterfowl hunting regulations is conducted annually in the United States (Blohm 1989). This process involves a number of meetings where the status of waterfowl is reviewed by the agencies responsible for setting hunting regulations. In addition, the U.S. Fish and Wildlife Service (USFWS) publishes proposed regulations in the Federal Register to allow public comment. This document is part of a series of reports intended to support development of harvest regulations for the 2003 hunting season. Specifically, this report is intended to provide waterfowl managers and the public with information about the use of adaptive harvest management …

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American Woodcock Population Status, 2003, James R. Kelley Jr. Jan 2003

American Woodcock Population Status, 2003, James R. Kelley Jr.

United States Fish and Wildlife Service: Publications

Singing-ground and Wing-collection surveys were conducted to assess the population status of the American woodcock (Scolopax minor). Singing-ground Survey data indicated that the number of displaying woodcock in the Eastern and Central Regions were unchanged from 2002 (P>0.1), although the point estimates of the trends were positive. Trends from the Singing-ground Survey during 1993-03 were –1.3 and –1.6% per year for the Eastern and Central regions, respectively (P<0.05). There were long-term (1968-03) declines (P<0.01) of 2.3% per year in the Eastern Region and 1.8% per year in the Central Region. The 2002 recruitment index for the Eastern Region (1.4 immatures per adult female) was the same as the 2001 index, but was 18% below the long-term regional average. The 2002 recruitment index for the Central Region (1.6 immatures per adult female) was 17% higher than the 2001 index (1.3 immatures per adult female), and was similar to the long-term regional average. The index of daily hunting success in the Eastern Region increased slightly from 1.8 woodcock per successful hunt in 2001 to 1.9 in 2002, but seasonal hunting success declined from 6.9 woodcock per successful hunter in 2001 to 6.6 in 2002. In the Central Region, the daily success index was 2.1 woodcock per successful hunt in 2001 and 2002; but seasonal hunting success increased from 10.0 woodcock per successful hunter in 2001 to 11.0 in 2002.

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Groundwater Flow Andwater Quality – A Flowpath Study In The Seminolewell Field, Cedar Rapids, Iowa, Douglas J. Schnoebelen, Michael J. Turco, John D. North Jan 2003

Groundwater Flow Andwater Quality – A Flowpath Study In The Seminolewell Field, Cedar Rapids, Iowa, Douglas J. Schnoebelen, Michael J. Turco, John D. North

United States Geological Survey: Staff Publications

In Iowa, alluvial aquifers near major rivers are a source of water for many communities. The City of Cedar Rapids withdraws water from wells completed in the Cedar River alluvium, a shallow alluvial aquifer adjacent to the Cedar River. The City of Cedar Rapids is located within Linn County in east-central Iowa, and water for the City is supplied by four well fields (East, Northwest, Seminole, and West well fields) along the Cedar River. The City has a population of about 121,000, and several large industries are major water users. Currently, per capita water usage in the City is nearly …

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Herbicide Loading To Shallow Ground Water Beneath Nebraska’S Management Systems Evaluation Area, Roy F. Spalding, Darrell G. Watts, Daniel D. Snow, David A. Cassada, Mary E. Exner, James S. Schepers Jan 2003

Herbicide Loading To Shallow Ground Water Beneath Nebraska’S Management Systems Evaluation Area, Roy F. Spalding, Darrell G. Watts, Daniel D. Snow, David A. Cassada, Mary E. Exner, James S. Schepers

Nebraska Water Center: Faculty Publications

Better management practices can counter deterioration of ground water quality. From 1991 through 1996 the influence of improved irrigation practices on ground water pesticide contamination was assessed at the Nebraska Management SystemsEvaluation Area. Three 13.4-ha corn (Zea mays L.) fields were studied: a conventional furrow-irrigated field, a surge-irrigated field and a center pivot–irrigated field, and a center pivot–irrigated alfalfa (Medicago sativa L.) field. The corn fields received one identical banded application of Bicep (atrazine [6-chloro-N-ethyl-N’-(1-methylethyl)-1,3,5-triazine-2,4,-diamine] _ metolachlor [2-chloro-N-(2-ethyl-6-methylphenyl)-N-(2-methoxy-1-methylethyl) acetamide]) annually; the alfalfa field was untreated. Ground water samples were collected …

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Herbicides In Ground Water Beneath Nebraska’S Management Systems Evaluation Area, Roy F. Spalding, Mary E. Exner, Daniel D. Snow, David A. Cassada, Mark E. Burbach, Stephen J. Monson Jan 2003

Herbicides In Ground Water Beneath Nebraska’S Management Systems Evaluation Area, Roy F. Spalding, Mary E. Exner, Daniel D. Snow, David A. Cassada, Mark E. Burbach, Stephen J. Monson

Nebraska Water Center: Faculty Publications

Profiles of ground water pesticide concentrations beneath the Nebraska Management Systems Evaluation Area (MSEA) describe the effect of 20 years of pesticide usage on ground water in the central Platte Valley of Nebraska. During the 6-yr (1991–1996) study, 14 pesticides and their transformation products were detected in 7848 ground water samples from the unconfined water table aquifer. Triazine and acetamide herbicides applied on the site and their transformation products had the highest frequencies of detection. Atrazine [6-chloro-N-ethyl-N’-(1-methylethyl)-1,3,5-triazine-2,4,-diamine] concentrations decreased with depth and ground water age determined with 3H/3He dating techniques. Assuming equivalent atrazine …

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Master Of Science Degree Programs 2003-2005, Nova Southeastern University Jan 2003

Master Of Science Degree Programs 2003-2005, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

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Graduate School Of Computer And Information Sciences 2003, Nova Southeastern University Jan 2003

Graduate School Of Computer And Information Sciences 2003, Nova Southeastern University

College of Engineering and Computing Course Catalogs

No abstract provided.

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Stochastic Modeling Of Nonlinear Epidemiology, Sankar Bokka Jan 2003

Stochastic Modeling Of Nonlinear Epidemiology, Sankar Bokka

Electronic Theses and Dissertations

No abstract provided.

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Kerr-Resonance-Condition-Coupled Enhancement In Magneto-Optic Media, A. De, A. Puri Jan 2003

Kerr-Resonance-Condition-Coupled Enhancement In Magneto-Optic Media, A. De, A. Puri

Physics Faculty Publications

We derive an expression for cyclotron frequency ωc, which sets Re[ϵ+ϵ−]=1 in a magneto-optic (MO) substrate, at any incident photon energy. Thereby, at any desired part of the optical spectrum, large Kerr effects can be obtained, which are generally known to occur either at the free-charge-carrier-plasma-resonance frequency ωp, or at frequencies where active electronic transitions take place. Under these conditions, ωp is seen to play a very different role; it is seen that for any ω, the magnitude of the Kerr resonance in a single MO (InSb here) substrate increases …

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Ultrafine Nife2o4 Powder Fabricated From Reverse Microemulsion Process, Jiye Fang, Narayan Shama, Le Duc Tung, Eun Young Shin, Charles J. O'Connor, Kevin L. Stokes, Gabriel Caruntu, John B. Wiley, Leonard Spinu, Jinke Tang Jan 2003

Ultrafine Nife2o4 Powder Fabricated From Reverse Microemulsion Process, Jiye Fang, Narayan Shama, Le Duc Tung, Eun Young Shin, Charles J. O'Connor, Kevin L. Stokes, Gabriel Caruntu, John B. Wiley, Leonard Spinu, Jinke Tang

Physics Faculty Publications

NiFe2O4 ultrafine powder with high crystallinity has been prepared through a reverse microemulsion route. The composition in starting solution was optimized, and the resulting NiFe2O4 was formed at temperature of around 550–600 °C, which is much lower than that observed from the solid-state reaction. Magnetic investigation indicates that samples are soft-magnetic materials with low coercivity and with the saturation magnetization close to the bulk value of Ni ferrite.

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Multivariate Slash And Skew-Slash Distributions / By Fei Tan, Fei Tan Jan 2003

Multivariate Slash And Skew-Slash Distributions / By Fei Tan, Fei Tan

Electronic Theses and Dissertations

No abstract provided.

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Intersecting Set Systems, Jaromy Scott Kuhl Jan 2003

Intersecting Set Systems, Jaromy Scott Kuhl

Electronic Theses and Dissertations

No abstract provided.

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Time-Resolved, Low-Dimensional Estimation Of Open Cavity Flow, Nathan E. Murray Jan 2003

Time-Resolved, Low-Dimensional Estimation Of Open Cavity Flow, Nathan E. Murray

Electronic Theses and Dissertations

No abstract provided.

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A Comparison Of Lowess Normalization Methods On Microarray Data, Yuanyuan Ding Jan 2003

A Comparison Of Lowess Normalization Methods On Microarray Data, Yuanyuan Ding

Electronic Theses and Dissertations

No abstract provided.

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An Impedance Tube Investigation Of Thermoacoustics With A Multi-Phase Working Fluid, Daniel C. Brown Jan 2003

An Impedance Tube Investigation Of Thermoacoustics With A Multi-Phase Working Fluid, Daniel C. Brown

Electronic Theses and Dissertations

No abstract provided.

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