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2001

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Articles 2491 - 2520 of 3030

Full-Text Articles in Physical Sciences and Mathematics

Design Of A Laboratory Secondary Hazard Study, David A. Goldade, Peter J. Savarie, Jerome C. Hurley, Stanley A. Gaddis, John J. Johnston Jan 2001

Design Of A Laboratory Secondary Hazard Study, David A. Goldade, Peter J. Savarie, Jerome C. Hurley, Stanley A. Gaddis, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

Factors influencing the design and execution of a secondary hazard study are presented using the anticoagulant rodenticide, difethialone, as a model. Frequently, regulatory agencies require a determination of the potential hazard posed to non-target species by the application of pesticides. This hazard can occur through: 1) primary hazard, direct consumption of the bait or formulation containing the pesticide, or 2) secondary hazard, indirect consumption of the pesticide via ingestion of biological matrices such as animals or plants containing pesticide residues. In making this determination, the selection of appropriate test species as well as routes and level of exposure are critical. …

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Introduction To Pesticides And Wildlife, John J. Johnston Jan 2001

Introduction To Pesticides And Wildlife, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

A pesticide is a substance intended for destroying, repelling or mitigating any animal, microorganism or plant pest. While pesticides are commonly chemical agents, biological or physical agents can also be pesticides. Many people equate the term pesticide with insecticide. However, there are a plethora of pesticides for which insects are not the target pest. Examples include herbicides, fungicides, rodenticides, acaricides, larvacides, etc. Additionally, pesticides are not limited to toxicants, but also include repellents, attractants and growth regulators (1 ) .

Pesticides are nearly ubiquitous in today's world. In agriculture, insecticides, nematicides and herbicides are applied to plants and soil to …

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Ecotoxicological Risks Of Potential Toxicants For Brown Tree Snake Control On Guam, John J. Johnston, Richard E. Mauldin, Peter J. Savarie, Joseph E. Brooks, Thomas M. Primus Jan 2001

Ecotoxicological Risks Of Potential Toxicants For Brown Tree Snake Control On Guam, John J. Johnston, Richard E. Mauldin, Peter J. Savarie, Joseph E. Brooks, Thomas M. Primus

United States Department of Agriculture Wildlife Services: Staff Publications

The brown tree snake (Boiga irregularis) is a nocturnal, arboreal, rear-fanged, mildly venomous, colubrid snake which can reach lengths of up to 2.3 m and weigh as much as 2 kg(1). Originally, the species' range included the northern and eastern coasts of Australia, Papua New Guinea and nearby islands (2). It is believed that sometime in the 19501s, that snakes were inadvertently transported from New Guinea to Guam, where they proliferated (3). By the mid-1960’s, marked decreases in Guam's bird life were observed. By the mid-1980’s, snake densities were estimated at 50 to 100/hectare (13,000 to 26,000/sq mile), …

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Avian Use Of Various Bait Mixtures Offered In Harvested Cornfields During Spring Migration In South Dakota, George M. Linz, H. Jeffrey Homan, Ryan L. Wimberly Jan 2001

Avian Use Of Various Bait Mixtures Offered In Harvested Cornfields During Spring Migration In South Dakota, George M. Linz, H. Jeffrey Homan, Ryan L. Wimberly

United States Department of Agriculture Wildlife Services: Staff Publications

The avicide, DRC-1339, is used to cull populations of spring-migrating blackbirds in eastern South Dakota to reduce damage to ripening sunflower in late summer. We investigated non-target bird hazards associated with using various grain mixtures to attract blackbirds (Icteridae), especially red-winged blackbirds (Agelaius phoeniceus), to avicide-treated bait broadcast in harvested cornfields. During spring 1997 and 1998, we recorded the species and numbers of birds attracted to 0.2-ha plots baited with cracked corn and brown rice, fine-chipped sunflower meats and brown rice (1997 only), and unsupplemented brown rice. Unbaited plots were used as reference sites. In 1997 and 1998, …

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Chlorophacinone Residues In Rangeland Rodents: An Assessment Of The Potential Risk Of Secondary Toxicity To Scavengers, Thomas M. Primus, John D. Eisemann, George H. Matschke, Craig Ramey, John J. Johnston Jan 2001

Chlorophacinone Residues In Rangeland Rodents: An Assessment Of The Potential Risk Of Secondary Toxicity To Scavengers, Thomas M. Primus, John D. Eisemann, George H. Matschke, Craig Ramey, John J. Johnston

United States Department of Agriculture Wildlife Services: Staff Publications

Field studies were conducted in California to assess efficacy of chlorophacinone-treated steam-rolled oats for controlling rangeland rodents. An objective of these studies was to assess the potential hazards of chlorophacinone residues in rangeland rodent carcasses and livers to mammalian and avian scavengers, especially raptors. Belding's ground squirrels, valley pocket gophers and Microtus spp. carcasses collected during the efficacy studies were analyzed for chlorophacinone residues. The method limit of detection (MLOD) for liver and carcass tissue samples averaged 0.036 μg/g and 0.034 μg/g, respectively. Chlorophacinone residues in Belding's ground squirrel (n=62) liver and carcass tissue ranged from Microtus sp. (n=3) tissue …

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Pathology Of Brucellosis In Bison From Yellowstone National Park, Jack C. Rhyan, Thomas Gidlewski, Thomas J. Roffe, Keith Aune, L. Michael Philo, Darla R. Ewalt Jan 2001

Pathology Of Brucellosis In Bison From Yellowstone National Park, Jack C. Rhyan, Thomas Gidlewski, Thomas J. Roffe, Keith Aune, L. Michael Philo, Darla R. Ewalt

United States Department of Agriculture Wildlife Services: Staff Publications

Between February 1995 and June 1999, specimens from seven aborted bison (Bison bison) fetuses or stillborn calves and their placentas, two additional placentas, three dead neonates, one 2-wk-old calf, and 35 juvenile and adult female bison from Yellowstone National Park (USA) were submitted for bacteriologic and histopathologic examination. One adult animal with a retained placenta had recently aborted. Serum samples from the 35 juvenile and adult bison were tested for Brucella spp. antibodies. Twenty-six bison, including the cow with the retained placenta, were seropositive, one was suspect, and eight were seronegative. Brucella abortus biovar 1 was isolated from …

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Comparison Of Instream Methods For Measuring Hydrolic Conductivity In Sandy Streambeds, Matthew K. Landon, David L. Rus, F. Edwin Harvey Jan 2001

Comparison Of Instream Methods For Measuring Hydrolic Conductivity In Sandy Streambeds, Matthew K. Landon, David L. Rus, F. Edwin Harvey

United States Geological Survey: Staff Publications

Streambed hydraulic conductivity (K) values were determined at seven stream transects in the Platte River Basin in Nebraska using different instream measurement techniques.

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Asymptotic Inference In Censored Regression Models Revisited, Chihwa Kao Jan 2001

Asymptotic Inference In Censored Regression Models Revisited, Chihwa Kao

Center for Policy Research

This paper establishes that regressors in the models with censored dependent variables need not be bounded for the standard asymptotic results to apply. Thus, regressors that grow monotonically with the observation index may be acceptable. It also purports to provide an upper bound on the rate at which regressors may grow.

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Distributed Polarizability Of The Water Dimer: Field-Induced Charge Transfer Along The Hydrogen Bond, Marc In Het Panhuis, P L A Popelier, R W. Munn, J G. Angyan Jan 2001

Distributed Polarizability Of The Water Dimer: Field-Induced Charge Transfer Along The Hydrogen Bond, Marc In Het Panhuis, P L A Popelier, R W. Munn, J G. Angyan

Australian Institute for Innovative Materials - Papers

The topological partitioning of electronic properties approach at Hartree-Fock level is used to investigate charge transfer response in a water dimer. Distributed polarizability components are employed to calculate the change in electron density under external fields. Field-induced charge flow between the water monomers is most significant along the direction of the hydrogen bond. The molecular polarizability of the molecules in the dimer is reduced owing to formation of the hydrogen bond.

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Geometric Edge Barrier In The Shubnikov Phase Of Type Ii Superconductors, E Brandt Jan 2001

Geometric Edge Barrier In The Shubnikov Phase Of Type Ii Superconductors, E Brandt

Australian Institute for Innovative Materials - Papers

In type-II superconductors the magnetic response can be irreversible for two different reasons: vortex pinning and barriers to flux penetration. Even without bulk pinning and in the absence of a microscopic Bean–Livingston surface barrier for vortex penetration, superconductors of nonellipsoidal shape can exhibit a large geometric barrier for flux penetration. This edge barrier and the resulting irreversible magnetization loops and flux-density profiles are computed from continuum electrodynamics for superconductor strips and disks of constant thickness, both without and with bulk pinning. Expressions are given for the field of first flux entry Hen and for the reversibility field Hrev …

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Tractor Test 1781: White 8510, Agco Dt160, Agco Allis 9755, Nebraska Tractor Test Lab Jan 2001

Tractor Test 1781: White 8510, Agco Dt160, Agco Allis 9755, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Test 1794: White 8710 Also Agco Allis 9775 (Cummins Engine) Also Agco Dt200, Nebraska Tractor Test Lab Jan 2001

Test 1794: White 8710 Also Agco Allis 9775 (Cummins Engine) Also Agco Dt200, Nebraska Tractor Test Lab

Nebraska Tractor Tests

ABOUT THE TEST REPORT AND USE OF THE DATA The test data contained in this report are a tabulation of the results of a series of tests. Due to the restricted format of these pages, only a limited amount of data and not all of the tractor specifications are included. The full OECD report contains usually about 30 pages of data and specifications. The test data were obtained for each tractor under similar conditions and therefore, provide a means of comparison of performance based on a limited set of reported data. EXPLANATION OF THE TEST PROCEDURES Purpose The purpose of …

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Nebraska Summary 354: Agco Dt200 Diesel, Nebraska Tractor Test Lab Jan 2001

Nebraska Summary 354: Agco Dt200 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

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Nebraska Summary 355: Agco Dt225 Diesel, Nebraska Tractor Test Lab Jan 2001

Nebraska Summary 355: Agco Dt225 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

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Test 1791: John Deere 9400t Also 9420t 24 Speed, Nebraska Tractor Test Lab Jan 2001

Test 1791: John Deere 9400t Also 9420t 24 Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

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Test 1789: John Deere 9200 24 & 12 Speed, Nebraska Tractor Test Lab Jan 2001

Test 1789: John Deere 9200 24 & 12 Speed, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

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Test 1796: Case Ih Stx 275/New Holland Tj 275 Diesel, Nebraska Tractor Test Lab Jan 2001

Test 1796: Case Ih Stx 275/New Holland Tj 275 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

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Test 1797: Case Ih Stx 325/New Holland Tj 325 Diesel, Nebraska Tractor Test Lab Jan 2001

Test 1797: Case Ih Stx 325/New Holland Tj 325 Diesel, Nebraska Tractor Test Lab

Nebraska Tractor Tests

No abstract provided.

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Evolving Tenure Rights And Agricultural Intensification In Southwestern Burkina Faso, Michael Kevane, Leslie C. Gray Jan 2001

Evolving Tenure Rights And Agricultural Intensification In Southwestern Burkina Faso, Michael Kevane, Leslie C. Gray

Economics

Popular and official representations of the environment in Burkina Faso present soils as fragile and potentially subject to catastrophic collapse in fertility. In the cotton growing zone of southwestern Burkina Faso, researchers and policy makers attribute changes in land cover and land quality to population growth. This paper presents evidence questioning the dominant "population-degradation narrative" as applied to Burkina. We find that farmers are intensifying their production systems. While population has led to land scarcity, farmers are responding to both the resulting uncertainty in land rights and reductions in soil quality by intensifying the production process. Investments are used both …

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Bedrock Geology And Sea-Level History Of Fayetteville Quadrangle, Washington County, Arkansas, Maria E. King, Jack T. King, Stephen K. Boss Jan 2001

Bedrock Geology And Sea-Level History Of Fayetteville Quadrangle, Washington County, Arkansas, Maria E. King, Jack T. King, Stephen K. Boss

Journal of the Arkansas Academy of Science

A digital map depicting the detailed bedrock geology of Fayetteville Quadrangle, Washington County, Arkansas was produced at 1:24,000 scale. This map was developed utilizing state-of-the-art Geographic Information Systems technology and represents the most detailed map of the geology of Fayetteville Quadrangle that has been produced. In addition, the stratigraphy was interpreted to develop a regional sea-level history for the quadrangle. The bedrock geology of Fayetteville Quadrangle consists of sedimentary rocks of the Mississippian and Pennsylvanian systems. The Mississippian System is represented by (in ascending order) the Boone, Batesville, Fayetteville, and Pitkin Formations. The Pennsylvanian System is represented by (in ascending …

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Geologic Hazards Associated With Shale Strata And Swelling Clays Within Fayetteville Quadrangle, Washington County, Arkansas, Maria E. King, Jack T. King, Stephen K. Boss Jan 2001

Geologic Hazards Associated With Shale Strata And Swelling Clays Within Fayetteville Quadrangle, Washington County, Arkansas, Maria E. King, Jack T. King, Stephen K. Boss

Journal of the Arkansas Academy of Science

No abstract provided.

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Searching For A Quantum Algorithm To Solve The Traveling Salesman Problem, Buckley Hopper Jan 2001

Searching For A Quantum Algorithm To Solve The Traveling Salesman Problem, Buckley Hopper

Honors Capstone Projects and Theses

No abstract provided.

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2001 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group Jan 2001

2001 File Geodatabase Containing Aerial Photos, Pete Reehling, Richard Mckenzie, City Of Tampa Department Of Sanitary Sewers Bay Study Group

Images

The Bay Study Group was created by the City of Tampa in 1976 to monitor the effects of pollution abatement that occurred in Hillsborough Bay when the city’s wastewater treatment plant was upgraded from primary to advanced treatment in 1979. The Bay Study Group documented a remarkable restoration of water quality parameters and biological indicators in Hillsborough Bay from the mid 1980s until 2009, when it was disbanded. This zip Geodatabase file contains the aerial photos for the year 2001.

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Remote Sensing Of Biotic Effects: Zebra Mussels (Dreissena Polymorpha) Influence On Water Clarity In Saginaw Bay, Lake Huron, Judith W. Budd, Thomas D. Drummer, Thomas F. Nalepa, Gary L. Fahnenstiel Jan 2001

Remote Sensing Of Biotic Effects: Zebra Mussels (Dreissena Polymorpha) Influence On Water Clarity In Saginaw Bay, Lake Huron, Judith W. Budd, Thomas D. Drummer, Thomas F. Nalepa, Gary L. Fahnenstiel

United States Department of Commerce: Staff Publications

In this study, Advanced Very High Resolution Radiometer (AVHRR) remote sensing reflectance (Rrs), imagery from 1987–1993 is used to study changes in water clarity before and after zebra mussels (Dreissena polymorpha) were discovered in Saginaw Bay, Lake Huron. Spatial and temporal trends in the data indicate distinct and persistent increases in water clarity in the inner bay after the first large recruitment of zebra mussels in the fall of 1991. The pre-Dreissena imagery show that turbidity in the inner bay was influenced by the Saginaw River discharge in spring, biological production (plankton) in summer, and …

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Changes In Diet And Body Condition Of Lake Whitefish In Southern Lake Michigan Associated With Changes In Benthos, Steven A. Pothoven, Thomas F. Nalepa, Philip J. Schneeberger, Stephen B. Brandt Jan 2001

Changes In Diet And Body Condition Of Lake Whitefish In Southern Lake Michigan Associated With Changes In Benthos, Steven A. Pothoven, Thomas F. Nalepa, Philip J. Schneeberger, Stephen B. Brandt

United States Department of Commerce: Staff Publications

We evaluated the long-term trends of the benthic macroinvertebrate community (1980–1999) and biological attributes of lake whitefish Coregonus clupeaformis (1985–1999) in southeastern Lake Michigan. We also determined what food types were important to lake whitefish in an area where the amphipod Diporeia had not yet declined in 1998 and how the diet of lake whitefish changed as Diporeia declined during 1999–2000. Zebra mussels Dreissena polymorpha invaded the study area in 1992; Diporeia began to decline in 1993 and was nearly absent by 1999. The body condition of lake whitefish decreased after 1993 and remained low thereafter. The length at age …

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Zebra Mussel (Dreissena Polymorpha) Selective Filtration Promoted Toxic Microcystis Blooms In Saginaw Bay (Lake Huron) And Lake Erie, Henry A. Vanderploeg, James R. Liebig, Wayne W. Carmichael, Megan A. Agy, Thomas H. Johengen, Gary L. Fahnenstiel, Thomas F. Nalepa Jan 2001

Zebra Mussel (Dreissena Polymorpha) Selective Filtration Promoted Toxic Microcystis Blooms In Saginaw Bay (Lake Huron) And Lake Erie, Henry A. Vanderploeg, James R. Liebig, Wayne W. Carmichael, Megan A. Agy, Thomas H. Johengen, Gary L. Fahnenstiel, Thomas F. Nalepa

United States Department of Commerce: Staff Publications

Microcystis aeruginosa, a planktonic colonial cyanobacterium, was not abundant in the 2-year period before zebra mussel (Dreissena polymorpha) establishment in Saginaw Bay (Lake Huron) but became abundant in three of five summers subsequent of mussel establishment. Using novel methods, we determined clearance, capture, and assimilation rates for zebra mussels feeding on natural and laboratory M. aeruginosa strains offered alone or in combination with other algae. Results were consistent with the hypothesis that zebra mussels promoted blooms of toxic M. aeruginosa in Saginaw Bay, western Lake Erie, and other lakes through selective rejection in pseudofeces. Mussels exhibited high …

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Schrödinger Equation Solutions For Small R And Resulting Functional Relations, Harry A. Mavromatis Jan 2001

Schrödinger Equation Solutions For Small R And Resulting Functional Relations, Harry A. Mavromatis

Turkish Journal of Physics

The Schrödinger equation is examined for small r (i.e. one step beyond the limit r \rightarrow 0) for the cases V(r) \rightarrow r^k, (k>0), and V(r) \rightarrow r^{-k} (0

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Photospheric Line Profiles In Deneb (A2 Iae), Berahi̇tdi̇n Albayrak, Cemal Aydin, Dursun Koçer Jan 2001

Photospheric Line Profiles In Deneb (A2 Iae), Berahi̇tdi̇n Albayrak, Cemal Aydin, Dursun Koçer

Turkish Journal of Physics

In this study, the strong lines were examined to determine the effect of velocity gradient due to mass loss on the line profiles in the atmosphere of Deneb. The lines are formed in the optical depth range -1.14 < log \tau < -0.14. None were found to exibit any asymmetry.

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A Theoretical Model For The Non-Linear Susceptibility Of The Antiferromagnetic Systems, Beki̇r Özçeli̇k, Keri̇m Kiymaç, Ahmet Eki̇ci̇bi̇l Jan 2001

A Theoretical Model For The Non-Linear Susceptibility Of The Antiferromagnetic Systems, Beki̇r Özçeli̇k, Keri̇m Kiymaç, Ahmet Eki̇ci̇bi̇l

Turkish Journal of Physics

In this study, we have developed a general theoretical model, based upon the simple mean field model of N\'{e}el, for the non-linear response of an antiferromagnetic system. The results indicate that the odd order derivatives, (d^{2n + 1}m_{a})_{0} = (-d^{2n + 1}m_{b})_{0}, where n=1,2,3......, will diverge and the even order derivatives, (d^{2n}m_{a})_{0} = (d^{2n}m_{b})_{0} will vanish due to the symmetry of two sublattices, ``a'' and ``b'', forming the antiferromagnet. This model also supports our experimental results performed on two antiferromagnetic samples, namely, Cs_{2}MnCl_{4}.2H_{2}O and MnCl_{2}.4H_{2}O [1].

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Reliability Studies Of The Skew Normal Distribution, Nicole Dawn Brown Jan 2001

Reliability Studies Of The Skew Normal Distribution, Nicole Dawn Brown

Electronic Theses and Dissertations

It has been observed in various practical applications that data do not conform to the normal distribution, which is symmetric with no skewness. The skew normal distribution proposed by Azzalini(1985) is appropriate for the analysis of data which is unimodal but exhibits some skewness. The skew normal distribution includes the normal distribution as a special case where the skewness parameter is zero. In this thesis, we study the structural properties of the skew normal distribution, with an emphasis on the reliability properties of the model. More specifically, we obtain the failure rate, the mean residual life function, and the reliability …

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