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Summer 1995, Nsu Oceanographic Center Jan 1995

Summer 1995, Nsu Oceanographic Center

Currents

No abstract provided.


Spring 1995, Nsu Oceanographic Center Jan 1995

Spring 1995, Nsu Oceanographic Center

Currents

No abstract provided.


Idea Analysis For The Development Of Clinical Trial Strategies, Roberta S. Horowitz Jan 1995

Idea Analysis For The Development Of Clinical Trial Strategies, Roberta S. Horowitz

CCAC Theses and Dissertations

Idea Analysis was investigated to determine its ability to organize scientific information and explain the results of specialists' deliberations in designing new clinical trials. Ideas have long been recognized as the engine of creativity. By focusing on the capture of ideas from the scientific literature, idea analysis procedures enable the arrangement of the information into forms consistent with those developed by subject specialists. The most obvious example is the concept structure. Ideas containing a common frequently occurring term/phrase can be depicted as a primary node in the concept network. Related terms will appear as elements associated with that node. Ideas …


Nutrient Changes In Saginaw Bay, Lake Huron, After The Establishment Of The Zebra Mussel (Dreissena Polymorpha), Thomas H. Johengen, Thomas F. Nalepa, Gary L. Fahnenstiel, Greg Goudy Jan 1995

Nutrient Changes In Saginaw Bay, Lake Huron, After The Establishment Of The Zebra Mussel (Dreissena Polymorpha), Thomas H. Johengen, Thomas F. Nalepa, Gary L. Fahnenstiel, Greg Goudy

United States Department of Commerce: Staff Publications

Concentrations of particulate and dissolved nutrients in Saginaw Bay, Lake Huron, were examined relative to zebra mussel colonization which occurred summer 1991. The magnitude and spatial pattern of changes indicate that mussels had a significant impact on nutrients in Saginaw Bay. Annual means for total suspended solids, particulate organic carbon, particulate phosphorus, and particulate silica in the inner bay were significantly lower in 1992 and 1993 (post-zebra mussel) than in 1991 (pre-zebra mussel). Annual means decreased from 11.5 mg L-1, 1.45 mg C L-1 (121 µM), 20.4 µg P L-1(0.66 µM), and 1.52 mg SiO …


1995 Platte River Basin Ecosystem Symposium Proceedings Jan 1995

1995 Platte River Basin Ecosystem Symposium Proceedings

Water Current Newsletter

No abstract provided.


Audubon's Perspective On Coyotes, Dede Armentrout Jan 1995

Audubon's Perspective On Coyotes, Dede Armentrout

Coyotes in the Southwest: A Compendium of Our Knowledge (Symposium Proceedings, 1995)

Audubon has a membership which probably spans all views of coyotes (Canis latrans) Audubon's staff views coyotes as biologically appropriate predators in most of the Southwest. We believe that they can be an asset to a well-managed ranch, but that they can also cause localized depredation which must be answered.

Our members value predators, including coyotes, for their natural role in ecological systems, including their influence on prey species. Many of our members travel broadly and spend money to view wildlife, and consider it a treat to see and hear coyotes.


Freezing And Thawing Of Agricultural Soils: Implications For Soil, Water, And Air Quality, Brenton S. Sharratt, Keith E. Saxton, Jerry K. Radke Jan 1995

Freezing And Thawing Of Agricultural Soils: Implications For Soil, Water, And Air Quality, Brenton S. Sharratt, Keith E. Saxton, Jerry K. Radke

Journal of the Minnesota Academy of Science

Most agricultural lands in the USA are subject to subfreezing temperatures. Soil freezing and thawing affects both biotic and abiotic interactions and processes which vary with weather, soil type, land management, and topography. Soil fauna generally undergo physiological changes or rely on locomotion as a means of adapting to frozen soils. Managing faunal populations using soil management may be achievable with a better understanding of winter ecological processes. Many of the thermal, hydraulic, mechanical, and physical properties of soils are altered by freezing and thawing. Soil erosion may be accentuated by soil freezing and thawing as a result of changes …


Studies On Freezing And Thawing Soils In Iowa, Jerry K. Radke, Edwin C. Berry Jan 1995

Studies On Freezing And Thawing Soils In Iowa, Jerry K. Radke, Edwin C. Berry

Journal of the Minnesota Academy of Science

Frozen soils have a major influence on the cropping systems and farming practices in northern states. However, relatively little research has been done on the physical, chemical, and biological processes that occur in the field during the non-growing season. Experiments on frozen soils were started recently in Iowa to 1) study the effects of residue cover on soil freezing and thawing, 2) measure the movement of water and solutes and changes in soil structure due to freezing and thawing of repacked soil columns in the field, 3) test the SHAW (Simultaneous Heat And Water) model for its capability to predict …


Frozen Soils: A Perspective On Past And Future Research For Promoting Sustainable Agricultural Systems, Jerry K. Radke, Brenton S. Sharratt, W. Doral Kemper, Dale A. Bucks Jan 1995

Frozen Soils: A Perspective On Past And Future Research For Promoting Sustainable Agricultural Systems, Jerry K. Radke, Brenton S. Sharratt, W. Doral Kemper, Dale A. Bucks

Journal of the Minnesota Academy of Science

Frozen soils impact many industries which rely· on soil, water, and .air resources in developing and manufacturing products. Most noteworthy is the agricultural industry in the northern United States where soils, which sustain food and fiber production, are subjected to frequent freezing and thawing. Soil freezing and thawing influences soil erodibility, surface and ground water quality, air quality, and biological activity. Many strides toward understanding frozen soil processes and managing lands to minimize the adverse effects of freezing and thawing have been made over the last two decades. Yet, further efforts to identify frozen soil processes which influence wind and …


Morphological Indicators Of Seasonally-Saturated Soils For A Hydrosequence In Southeastern Minnesota, J. C. Bell, J. A. Thompson, C. A. Butler Jan 1995

Morphological Indicators Of Seasonally-Saturated Soils For A Hydrosequence In Southeastern Minnesota, J. C. Bell, J. A. Thompson, C. A. Butler

Journal of the Minnesota Academy of Science

The duration and depth of seasonal soil saturation affects soil suitability for many landuses and are critical factors in the determination of hydric soil boundaries for jurisdictional wetland delineations. Biochemical processes in saturated, anaerobic soil conditions lead to the genesis of soil morphological features that indicate the duration of seasonal saturation. However, few prior studies confirm the relationships between soil hydrology and soil morphology in Minnesota landscapes. We monitored water table and piezometric elevations, soil temperature, redox potential, and soil matric potential at multiple depths for five locations along a hillslope hydrosequence of well to very poorly drained prairie soils …


Influence Of Vegetated Wetlands On The Water Quality Of Two Glacial Prairie Lakes, Lois Haertel, Walter G. Duffy, Daniel E. Kokesh Jan 1995

Influence Of Vegetated Wetlands On The Water Quality Of Two Glacial Prairie Lakes, Lois Haertel, Walter G. Duffy, Daniel E. Kokesh

Journal of the Minnesota Academy of Science

We investigated the influence of vegetated wetlands on water quality of two eastern South Dakota glacial prairie lakes. Surface water from a 5,880 ha pastured basin drains into a 90 ha upstream Typha wetland and enters Lake Enemy Swim passing 400 m through Typha-Scirpus littoral wetland. A second 1,290 ha basin characterized by row crops and pasture drains into a 260 ha open water slough entering L. Enemy Swim adjacent to Typha-Scirpus littoral wetland. Water enters Lake Cochrane from two smaller drainage basins. Water from a 180 ha basin consisting of a pasture and wet meadow enters the lake after …


Fisheries And Oceanography Off Galicia, Nw Spain: Mesoscale Spatial And Temporal Changes In Physical Processes And Resultant Patterns Of Biological Productivity, K. R. Tenore, M. Alonsonval, L. P. Atkinson, J. M. Cabanas, R. M. Cal, H. J. Campos, F. Castillejo, E. J, Chesney, N. Gonzalez, R. B. Hanson, C. R. Mcclain, A. Miranda, M. R. Roman, J. Sanchez, G. Santiago, L. Valdes, M. Varela, J. Yoder Jan 1995

Fisheries And Oceanography Off Galicia, Nw Spain: Mesoscale Spatial And Temporal Changes In Physical Processes And Resultant Patterns Of Biological Productivity, K. R. Tenore, M. Alonsonval, L. P. Atkinson, J. M. Cabanas, R. M. Cal, H. J. Campos, F. Castillejo, E. J, Chesney, N. Gonzalez, R. B. Hanson, C. R. Mcclain, A. Miranda, M. R. Roman, J. Sanchez, G. Santiago, L. Valdes, M. Varela, J. Yoder

CCPO Publications

The Galician shelf off NW Spain (43N degrees 9W degrees) exhibits mesoscale spatial and temporal changes in biological productivity associated with upwelling. Spatial heterogeneity results from local geomorphic and land-sea interactions superimposed on the large scale atmospheric processes that produce upwelling. Wind-induced upwelling events, commonly of short (i.e., week) duration, are more common in the summer than in the winter. A Series of cruises, including some time series sampling, and satellite imagery analysis showed that surface upwelling was more common and persistent on the northern coast compared with the western coast off the coastal embayments, the Rias Bajas. Nearshore off …


Nebraska Summary: S197 Massey Ferguson 8120, Nebraska Tractor Test Lab Jan 1995

Nebraska Summary: S197 Massey Ferguson 8120, 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 …


Some Relationships Between Sedimentary Trace Metal Concentrations And Freshwater Phytoplankton And Sedimentary Diatom Species Composition, Allan Hayes Vogel Jan 1995

Some Relationships Between Sedimentary Trace Metal Concentrations And Freshwater Phytoplankton And Sedimentary Diatom Species Composition, Allan Hayes Vogel

Dissertations and Theses

Sediments from 21 Oregon lakes were analyzed for seven metals (Fe, Mn, Zn, Cu, Co, Ni, V) in three forms (exchangeable, organic+sulfides, and oxyhydroxides+ oxides+ carbonates) using a sequential fractionation procedure. The summer epilimnetic filterable concentration of an eighth (Mo) was also determined. Sedimentary diatom remains and summer phytoplankton populations of the lakes were correlated with the 22 metal parameters and with conservative water chemistry parameters, estimators of lake productivity, and watershed geology. Both the sedimentary metals and the two populations of primary producers correlated best with the ecoregions of Omernik and Gallant (1986). A number of species possessed correlations …


Fermi Problems: Educated Guesses, John A. Adam Jan 1995

Fermi Problems: Educated Guesses, John A. Adam

Mathematics & Statistics Faculty Publications

No abstract provided.


Avian Use Of Riparian Corridors And Adjacent Cropland In East-Central Nebraska, Rebecca L. Fitzmaurice Jan 1995

Avian Use Of Riparian Corridors And Adjacent Cropland In East-Central Nebraska, Rebecca L. Fitzmaurice

School of Natural Resources: Dissertations, Theses, and Student Research

No abstract provided.


Helical Stacking In Dna 3-Way Junctions Containing 2 Unpaired Pyrimidines - Proton Nmr-Studies, Neocles B. Leontis, Michael T. Hills, Martial Piotto, Igor V. Ouporov, Arun Malhotra, David G. Gorenstein Jan 1995

Helical Stacking In Dna 3-Way Junctions Containing 2 Unpaired Pyrimidines - Proton Nmr-Studies, Neocles B. Leontis, Michael T. Hills, Martial Piotto, Igor V. Ouporov, Arun Malhotra, David G. Gorenstein

Chemistry Faculty Publications

The proton NMR spectra of DNA three-way junction complexes (TWJ) having unpaired pyrimidines, 5'-TT- and 5'-TC- on one strand at the junction site were assigned from 2D NOESY spectra acquired in H2O and D2O solvents and homonuclear 3D NOESY-TOCSY and 3D NOESY-NOESY in D2O solvent. TWJ are the simplest branched structures found in biologically active nucleic acids. Unpaired nucleotides are common features of such structures and have been shown to stabilize junction formation. The NMR data confirm that the component oligonucleotides assemble to form conformationally homogeneous TWJ complexes having three double-helical, B-form arms. Two of the helical arms stack upon …


The Palmer Lter: A Long-Term Ecological Research Program At Palmer Station, Antarctica, Raymond C. Smith, Karen S. Baker, William R. Fraser, Eileen E. Hofmann, David M. Karl, John M. Klinck, Langdon B. Quetin, Barbara B. Prezelin, Robin M. Ross, Wayne Z. Trivelpiece, Maria Vernet Jan 1995

The Palmer Lter: A Long-Term Ecological Research Program At Palmer Station, Antarctica, Raymond C. Smith, Karen S. Baker, William R. Fraser, Eileen E. Hofmann, David M. Karl, John M. Klinck, Langdon B. Quetin, Barbara B. Prezelin, Robin M. Ross, Wayne Z. Trivelpiece, Maria Vernet

CCPO Publications

THE ANTARCTIC marine ecosystem-the assemblage of plants, animals, ocean, sea ice, and island components south of the Antarctic Convergence is among the largest readily defined ecosystems on Earth (36 X 106 km2 ) (Hedgpeth, 1977; Petit et al., 1991). This ecosystem is composed of an interconnected system of functionally distinct hydrographic and biogeochemical subdivisions (Treguer and Jacques, 1992) and includes open ocean, frontal regions, shelf-slope waters, sea ice, and marginal ice zones. Oceanic, atmospheric, and biogeochemical processes within this system are thought to be globally significant, have been infrequently studied, and are poorly understood relative to more accessible marine ecosystems …


Electrochemical, Chromatographic, And Spectrometric Studies Of An Osmium Containing Polymer, Lawrence John Rhodes Jan 1995

Electrochemical, Chromatographic, And Spectrometric Studies Of An Osmium Containing Polymer, Lawrence John Rhodes

Master's Theses

No abstract provided.


Modern Marine Sediments Of Bahia Concepcion: Patterns, Processes, And Potential Analogues To Neogene Rift Basin Deposits Of Baja California, Timothy William Reardon Jan 1995

Modern Marine Sediments Of Bahia Concepcion: Patterns, Processes, And Potential Analogues To Neogene Rift Basin Deposits Of Baja California, Timothy William Reardon

Honors Papers

Neogene strata in Baja California preserve a record of extensional basins produced during early phases of rifting in the Gulf of California. This actualistic study addresses the feasibility of using Holocene sediments of Bahia Concepcion - a rift basin forming a shallow marine bay In southern Baja California - as analogues for the interpretation of Neogene strata in the Pliocene Loreto Basin. Three major lithofacies occur in Bahia Concepcion: Mud sediments dominate most of the central portion of the bay. Moderately sorted sands occur adjacent to shorelines formed by coalesced alluvial fans and a broad alluvial plain, while carbonate sands …


Recreational And Angler Survey Of The Buffalo National River, Arkansas, James E. Johnson Jan 1995

Recreational And Angler Survey Of The Buffalo National River, Arkansas, James E. Johnson

Journal of the Arkansas Academy of Science

The Buffalo River in northern Arkansas was surveyed for recreator and angler use in 1991 and 1992. The river was divided into three reaches and numbers of boats, recreators, anglers, and catches were compiled by creel clerks at nine selected take-out points. Outfitter rental receipts were used to estimate rental boats, and the proportion of rental to private boats creeled was used to correct for private boats not counted on the rental receipts. A total of 1,656 boats containing 3,071 recreators was contracted by the creel clerks during 1991 and 1992; 9.2% of the recreators were anglers. Expansion of the …


Impacts Of Irrigation Development On Anadromous Fish In The Yakima River Basin, Washington, Robert L. Tuck Jan 1995

Impacts Of Irrigation Development On Anadromous Fish In The Yakima River Basin, Washington, Robert L. Tuck

All Master's Theses

Prior to Euroamerican development, the Yakima River Basin was a major producer of salmon. Total runs of approximately 800,000 have declined to 3,000-5,000, or less than 1% of original run size. Three species are extinct in the basin, including summer chinook, coho, and sockeye.

Irrigation development, including the construction of unscreened diversions, the blockage of spawning and rearing habitat by reservoir dams, and the dewatering of spawning and rearing habitat, began in the mid-1800's and today totals approximately 500,000 acres. Historical records provide a wealth of information documenting irrigation development and its consequences on anadromous fish populations.


Structure And Function Of Magnetosomes In Magnetotactic Bateria, Richard B. Frankel, Dennis A. Bazylinski Jan 1995

Structure And Function Of Magnetosomes In Magnetotactic Bateria, Richard B. Frankel, Dennis A. Bazylinski

Physics

Magnetotactic bacteria contain magnetosomes, which are mineral particles enclosed my membranes. The particles are ferrimagnetic magnetite, ferrimagnetic greigite, or greigite and non-magnetic pyrite. The particles constitute an elegant biomagnetic compass that orients the cell along the geomagnetic field lines as it swims. This paper discusses the structures of these particles and their possible formation mechanisms.


Mississippi River Flood Waters That Reached The Gulf Stream, Peter B. Ortner, Thomas N. Lee, Peter J. Milne, Rod G. Zika, M. Elizabeth Clarke, Guillermo P. Podesta, Peter K. Swart, Patricia A. Tester, Larry P. Atkinson, Walter R. Johnson Jan 1995

Mississippi River Flood Waters That Reached The Gulf Stream, Peter B. Ortner, Thomas N. Lee, Peter J. Milne, Rod G. Zika, M. Elizabeth Clarke, Guillermo P. Podesta, Peter K. Swart, Patricia A. Tester, Larry P. Atkinson, Walter R. Johnson

CCPO Publications

Distributions of physical, biological, and chemical parameters in Florida Keys coastal waters seaward of the reef track were surveyed on September 9 to 13, 1993, as part of a coordinated multidisciplinary study of surface transport processes. A band of low-salinity water was observed along the shoreward side of the Florida Current over the downstream extent of the survey from Miami to Key West. Biological and chemical indicators within the band, together with its large volume, satellite imagery, and a surface drifter trajectory suggested the recent Mississippi River flood as the source.


Land Management Report For The Kent River Catchment, Sue Kelly Jan 1995

Land Management Report For The Kent River Catchment, Sue Kelly

Natural resources published reports

The Kent River Catchment is located in the South-West of Western Australia, approximately between latitudes 34° 15' and 35° 10' South and longitudes 116° 45" and 117° 50° East. The north-eastern boundary of the catchment stretches to the Albany Highway at Tenterden, and from there the catchment curves towards Rocky Gully before continuing to the South Coast (Figure 1.1.1). The catchment is located within the Shires of Cranbrook, Plantagenet and Denmark.

The Kent River Catchment is part of Basin 604, which is the Water Authority descriptor for the Kent, Bow and Kordabup River catchments collectively. Basin 604 has a total …


Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie Jan 1995

Proline Concentration As An Indicator Of The Level Of Salt Tolerance, Philomena Y. Rosalie

Theses : Honours

Each year approximately 20 million hectares of land become affected by increasing salinity. Salt tolerant plants are being used to rehabilitate salt affected areas. Plants use a variety of mechanisms to adapt to salt in their environments. Glycophytes tolerate low to moderate levels of salt while halophytes can tolerate very high salt levels. Many basic physiological attributes have been suggested as important components of a salt tolerant phenotype. These include, influx and/or efflux of ions across plasma membrane and the tonoplast, modification of membrane composition and synthesis of compatible solutes such as soluble carbohydrates, glycine betaines and proline. The project …


Initial Transgressive Phase Of Leg 144 Guyots: Evidence Of Extreme Sulfate Reduction, Bjørn Buchardt, Mary Anne Holmes Jan 1995

Initial Transgressive Phase Of Leg 144 Guyots: Evidence Of Extreme Sulfate Reduction, Bjørn Buchardt, Mary Anne Holmes

Department of Earth and Atmospheric Sciences: Faculty Publications

The initial transgressive phase at the Leg 144 Guyots is characterized by a typical association of sedimentary facies (from bottom to top): in situ weathered volcanic rocks; variegated clays, partly pyritic; gray clay, pyritic, homogeneous, or mottled; black clay, peaty, laminated, or bioturbated; and marine argillaceous limestone. Site 877 at Wodejebato Guyot represents the typical development of the initial transgressive phase. The black clay is rich in organic carbon (up to 40%) and sulfur (up to 25%). The organic matter is dominantly of terrestrial origin, but it has a significant marine, algal input. The variegated clays consist of a red, …


Nebraska Summary: S195 Caterpillar Challenger 45, Nebraska Tractor Test Lab Jan 1995

Nebraska Summary: S195 Caterpillar Challenger 45, 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 …


Nebraska Summary: S194 Caterpillar Challenger 35, Nebraska Tractor Test Lab Jan 1995

Nebraska Summary: S194 Caterpillar Challenger 35, 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 …


Nebraska Summary: S198 Massey Ferguson 8140, Nebraska Tractor Test Lab Jan 1995

Nebraska Summary: S198 Massey Ferguson 8140, 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 …