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Gulf Stream Frontal Eddy Influence On Productivity Of The Southeast United States Continental Shelf, Thomas N. Lee, James A. Yoder, Larry P. Atkinson Jan 1991

Gulf Stream Frontal Eddy Influence On Productivity Of The Southeast United States Continental Shelf, Thomas N. Lee, James A. Yoder, Larry P. Atkinson

CCPO Publications

Weekly period meanders and eddies are persistent features of Gulf Stream frontal dynamics from Miami, Florida, to Cape Hatteras, North Carolina. Satellite imagery and moored current and temperature records reveal a spatial pattern of preferred regions for growth and decay of frontal disturbances. Growth regions occur off Miami, Cape Canaveral, and Cape Fear due to baroclinic instability, and decay occurs in the confines of the Straits of Florida between Miami and Palm Beach, between 30° and 32°N where the stream approaches the topographic feature known as the Charleston bump and between 33°N and Cape Hatteras. Eddy decay regions are associated …

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Nebraska Summary: S100 John Deere 3055, Nebraska Tractor Test Lab Jan 1991

Nebraska Summary: S100 John Deere 3055, 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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Late Holocene Paleoseismicity Along The Northern Oregon Coast, Mark Edward Darienzo Jan 1991

Late Holocene Paleoseismicity Along The Northern Oregon Coast, Mark Edward Darienzo

Dissertations and Theses

Marsh paleoseismological studies were conducted in four bays (Necanicum, Nestucca, Siletz, and Yaquina) along the northern Oregon coast and compared with completed studies in two other bays (Netarts and Alsea). Coseismically buried peats were identified in all bays, based on 1) abrupt contacts, decreases in organic content, increases in sand content, increases in beach sand, and changes in diatom assemblages, all from the peat to the overlying sediments, 2) distinct sandy layers and key plant macrofossils, such as Triglochin, above the buried peat, and 3) widespread correlation of the buried peats within the bay. The stratigraphy and the ages and …

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Self-Activation And Inhibition: A Simple Nonlinear Model, J. A. Adam Jan 1991

Self-Activation And Inhibition: A Simple Nonlinear Model, J. A. Adam

Mathematics & Statistics Faculty Publications

Self-activation and self-inhibition of cell number density (or growth factor concentration) due to a spatially localized source are studied. Both the time-independent and time-dependent models are examined, and the linear stability of the resulting three steady states of the former is discussed.

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Activator-Inhibitor Control Of Tissue Growth, John A. Adam Jan 1991

Activator-Inhibitor Control Of Tissue Growth, John A. Adam

Mathematics & Statistics Faculty Publications

This note develops a simple model for the competition between activator and inhibitor control mechanisms in one-dimensional tissue growth. The pedagogic usefulness of such a model is that it is easily accessible to undergraduate applied mathematicians and is suggestive of behavior known to occur in more realistic biological systems (e.g., some types of cancer). The limitations of the model are obvious and can provide a basis for discussion of the applicability of complementary levels of description in mathematical modeling.

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Potential Effects Of Climate Change On Milk Production And Conception Rate In Dairy Cattle In The United States And Western Europe, Peggy Lea Klinedinst Jan 1991

Potential Effects Of Climate Change On Milk Production And Conception Rate In Dairy Cattle In The United States And Western Europe, Peggy Lea Klinedinst

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

No abstract provided.

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Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate Jan 1991

Deep Tillage : Keep An Eye On Costs As Well As Yields, Amir Abadi, Andrew Bathgate

Journal of the Department of Agriculture, Western Australia, Series 4

Deep tillage overcomes compaction of sandy soils caused by movement of heavy machinery. Many experiments since 1981 have shown cereal yields improve as a result of deep tillage. However, the increased yield does not necessarily mean more profit when costs are taken into account. To determine the profitability of deep tillage farmers must consider its impact on other farm operations. A whole-farm analysis is needed to accurately determine the increase in profit resulting from deep tillage

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Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders Jan 1991

Wildlife Corridors In The Wheatbelt, Richard Hobbs, Denis Saunders

Journal of the Department of Agriculture, Western Australia, Series 4

Native vegetation in the Western Australian wheatbelt now persists mostly in small areas that remained uncleared for various reasons. (See 'Remnant vegetation on farms is a valuable resource' on page 43.) On their own, most of these remnant areas are difficult to manage, and too small to retain viable populations of many of the birds and other animals found in the wheatbelt. These patches of vegetation can be linked by wildlife corridors, which may increase the ability of the wildlife to move about and persist in the area

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Glacial Deposits, Vol. 19, 1990-1991, Department Of Geography-Geology Jan 1991

Glacial Deposits, Vol. 19, 1990-1991, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology

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The Effect Of Age Misreporting In China On The Calculation Of Mortality Rates At Very High Ages, Ansley J. Coale, Shaomin Li Jan 1991

The Effect Of Age Misreporting In China On The Calculation Of Mortality Rates At Very High Ages, Ansley J. Coale, Shaomin Li

Management Faculty Publications

When mortality rates by age are calculated from recorded deaths and enumerated populations, rates at higher ages are typically in error because of misstated ages. Mortality rates for China in 1981 have been calculated from the number of deaths in 1981 in each household recorded in the 1982 census, and from the census population back-projected one year. Because age was determined from date of birth, and because persons of the Chinese culture have very precise knowledge of date of birth, the mortality rates even at high ages should be unusually accurate. This expectation is fulfilled for most of China, but …

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An Examination And Analysis Of The Boltzmann Machine, Its Mean Field Theory Approximation, And Learning Algorithm, Vincent Clive Phillips Jan 1991

An Examination And Analysis Of The Boltzmann Machine, Its Mean Field Theory Approximation, And Learning Algorithm, Vincent Clive Phillips

Theses : Honours

It is currently believed that artificial neural network models may form the basis for inte1ligent computational devices. The Boltzmann Machine belongs to the class of recursive artificial neural networks and uses a supervised learning algorithm to learn the mapping between input vectors and desired outputs. This study examines the parameters that influence the performance of the Boltzmann Machine learning algorithm. Improving the performance of the algorithm through the use of a naïve mean field theory approximation is also examined. The study was initiated to examine the hypothesis that the Boltzmann Machine learning algorithm, when used with the mean field approximation, …

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Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright Jan 1991

Groundwater Hydrology Of A Population Of Lindera Melissifolia In Arkansas, J. Dainette Priest, Robert D. Wright

Journal of the Arkansas Academy of Science

Groundwater hydrology was monitored from October through August in and around a bottomland forest pond containing Lindera melissifolia, pondberry. The study site exhibited a series of low ancient dunes and depressions, with seasonal ponds in the depressions. Ponds showed no surface inlets or outlets. Shallow wells were made and soil cores removed along a transect from the top of one dune across the pond to a lower dune. Piezometers were installed in the wells and groundwater levels monitored. Soil core samples were analyzed to determine particle size distribution at soil profile positions selected during field analysis. It was shown that …

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Direct Determination Of Molecular-Orbital Symmetry Of H2s Using Polarized X-Ray Emission, R. Mayer, Dennis W. Lindle, S. H. Southworth, P. L. Cowan Jan 1991

Direct Determination Of Molecular-Orbital Symmetry Of H2s Using Polarized X-Ray Emission, R. Mayer, Dennis W. Lindle, S. H. Southworth, P. L. Cowan

Chemistry and Biochemistry Faculty Research

X-ray emission from the molecule H2S is strongly polarized following excitation of a sulfur K-shell electron to an unoccupied subthreshold molecular orbital with a polarized x-ray beam. Changes in the polarization of the emission spectrum are observed as the incident beam's energy is swept across the subthreshold absorption resonance. The previously unresolved absorption resonance is shown experimentally to be primarily associated with a molecular orbital of b2 symmetry, but with a high-excitation-energy component due to an orbital with a1 symmetry. Satellite emission intensity is shown to depend on the primary photon energy and is therefore associated …

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Metabolic Efficiency And Regulation Of Body Weight: A Comparison Between Life In Hypogean And Epigean Ecosystems, Jayant Biswas Jan 1991

Metabolic Efficiency And Regulation Of Body Weight: A Comparison Between Life In Hypogean And Epigean Ecosystems, Jayant Biswas

International Journal of Speleology

In the present study metabolic efficiency in the epigean and hypogean populations of Nemacheilus evezardi (Day) was examined. Different experiments were conducted, in both populations, by keeping them either in restricted oxygen or restricted feeding conditions, including starvation. Results clearly show that the rate of oxygen consumption for the hypogean population was significantly less as compared to its epigean counterpart. Further, results also suggest that the hypogean population has a tremendous capacity to maintain its metabolic activity and regulate its body weight under severe conditions characterized by an absence or a limited supply of food.

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Revision Of The Genus Troglophilus (Orthoptera, Rhaphidophoridae) In Crete, Greece, Dimitrios Kollaros, Kaloust Paragamian, Anastassios Legakis Jan 1991

Revision Of The Genus Troglophilus (Orthoptera, Rhaphidophoridae) In Crete, Greece, Dimitrios Kollaros, Kaloust Paragamian, Anastassios Legakis

International Journal of Speleology

The genus Troglophilus (Orthoptera, Rhaphidophoridae) from Crete is revised using new data from specimens collected recently. The three previously reported species are considered to be only one, T. spinulosus, on the basis of morphological, ecological and distributional similarities. The species is more fully described and notes are given on its ecology.

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Observations On The Biology Of Spelaelacris Tabulae Peringuey (Orthoptera, Rhaphidophoridae), From The Wynberg Cave (Capetown, South Africa), Gianmaria Carchini, Claudio Di Russo, Mauro Rampini Jan 1991

Observations On The Biology Of Spelaelacris Tabulae Peringuey (Orthoptera, Rhaphidophoridae), From The Wynberg Cave (Capetown, South Africa), Gianmaria Carchini, Claudio Di Russo, Mauro Rampini

International Journal of Speleology

Data on the age structure, fecundity, egg morphology and feeding habits of the Spelaeiacris tabulae population from Wynberg cave are reported and compared with other Rhaphidophoridae species. S. tabulae shows a certain degree of adaptation to cave life, as usual in the other temperate species of Rhaphidophoridae.

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Population Size Of Pyrenean Troglobiont Coleopters (Speonomus Species) In A Cave In Belgium, Raymond Tercafs, Christine Brouwir Jan 1991

Population Size Of Pyrenean Troglobiont Coleopters (Speonomus Species) In A Cave In Belgium, Raymond Tercafs, Christine Brouwir

International Journal of Speleology

The population size of three troglobitic species of Speonomus (Coleoptera Bathysciinae) from the Pyrenees, intentionally introduced in 1969-1970 into the “Grotte de Ramioul” cave (Province of Liège, Belgium) has been studied using the mark-recapture technique. It has been shown that the three cave levels possess large Speonomus populations (upper network: 12,718; middle network: 13,902; lower network: 18,249 individuals) and that the superficial underground environment is also colonized, including the schist area. The most abundant species is Speonomus longicornis (relative frequency between 0.73 to 0.89). The two other species are present in the relative frequency between 0.04 and 0.23 for S. …

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Nebraska Summary: S104 Ford 4630 8x8, Nebraska Tractor Test Lab Jan 1991

Nebraska Summary: S104 Ford 4630 8x8, 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: S102 Ford 3430 8x8, Nebraska Tractor Test Lab Jan 1991

Nebraska Summary: S102 Ford 3430 8x8, 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: S101 John Deere 3255, Nebraska Tractor Test Lab Jan 1991

Nebraska Summary: S101 John Deere 3255, 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: S137 Zetor 9540, Nebraska Tractor Test Lab Jan 1991

Nebraska Summary: S137 Zetor 9540, 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: S338 Hurlimann 6135, Nebraska Tractor Test Lab Jan 1991

Nebraska Summary: S338 Hurlimann 6135, 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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Ice-Wedge Casts Of Wisconsinan Age In Eastern Nebraska, William J. Wayne Jan 1991

Ice-Wedge Casts Of Wisconsinan Age In Eastern Nebraska, William J. Wayne

Department of Earth and Atmospheric Sciences: Faculty Publications

Sand-filled, wedge-shaped structures beneath a thin layer of aeolian sand penetrate a preIllinoian till and gravel in northeastern Nebraska. Interpreted to be relic thermal contraction crack wedges, they provide the first definite evidence in this State of the former presence of permafrost. The wedges are 5- 7 m apart, 1.8-2.8 m deep and 0.6-0.9 m across at the top, taper downward to a crack and intersect to form polygons. They are filled with medium sand that contains mostly rounded and frosted grains. Vertical fabric is present in each wedge. Ventifacts lie along the top of the till, which is covered …

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Reservoir Sedimentation Studies, D C. Boudurant, R H. Livesey Jan 1991

Reservoir Sedimentation Studies, D C. Boudurant, R H. Livesey

United States Army Corps of Engineers, Omaha District

It must be recognized that, when a reservoir is constructed on a stream, all or most of the sediment transported into the reservoir by the stream will be deposited there. With few exceptions, there is no practical method for reducing or eliminating the sediment inflow; thus it is necessary to anticipate and to provide for resulting problems. The major problem is, of course, the accumulative loss of storage capacity. Other items of importance include the distribution of the sediment with respect to various storage increments, the effect on the chemical or physical quality of the water, ecological effects, and the …

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On The Normalized Yield (Events/Rad/Dalton) Of Biological Molecules Irradiated With Energetic Heavy Ions, Robert Katz Jan 1991

On The Normalized Yield (Events/Rad/Dalton) Of Biological Molecules Irradiated With Energetic Heavy Ions, Robert Katz

Robert Katz Publications

When irradiated with electrons or γ-rays, a number of biological molecules display an approximately linear relationship between the reciprocal of the D37 dose and molecular weight. This is conventionally plotted as a relation between target molecular weight and true molecular weight, where the target molecular weight Mt is given as: Mt × (D37) = α (1) where α is approximately 1010 Da-rad/eV of the energy assumed to be “deposited in the target” in a single “hit” for expression of the end-point. We emphasize that D37 is expressed in rads for we will later …

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Radial Distribution Of Dose, Robert Katz, Matesh N. Varma Jan 1991

Radial Distribution Of Dose, Robert Katz, Matesh N. Varma

Robert Katz Publications

The radial distribution of dose about the path of a heavy ion, principally from delta rays, is one of the central contributions of atomic physics to the systematization of high LET radiation effects in condensed matter, whether the detection arises in chemical, physical, or biological systems. In addition to the radial distribution of dose, we require knowledge of the response of the system to X-rays or gamma-rays or to beams of energetic electrons such that the electron slowing-down spectra from these radiations can approximate the slowing-down spectra from delta rays even at different radial distances from the ion's path. A …

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Cross Sections For Single And Double Strand Breaks In Sv-40 Virus In Eo Buffer After Heavy Ion Irradiation: Experiment And Theory, Robert Katz, S. Wesely Jan 1991

Cross Sections For Single And Double Strand Breaks In Sv-40 Virus In Eo Buffer After Heavy Ion Irradiation: Experiment And Theory, Robert Katz, S. Wesely

Robert Katz Publications

Measured cross sections after heavy ion bombardment, for both single and double strand breaks of SV-40 virus in EO buffer (which emphasizes indirect effects), are consistent with the theory of Butts and Katz for 1-hit detectors.

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Potential Impacts Of Biomass Production In The United States On Biological Diversity, James H. Cook, Jan Beyea, Kathleen H. Keeler Jan 1991

Potential Impacts Of Biomass Production In The United States On Biological Diversity, James H. Cook, Jan Beyea, Kathleen H. Keeler

School of Biological Sciences: Faculty Publications

Biomass could be a renewable source of energy and chemicals that would not add CO2 to the atmosphere. It will become economically competitive as its cost decreases relative to energy costs, and biotechnology is expected to accelerate this trend by increasing biomass productivity. Pressure to slow global warming may also make biomass more attractive. Substantial dependence on biomass would entail massive changes in land use, risking serious reductions in biodiversity through destruction of habitat for native species. Forests could be managed and harvested more intensively, and virtually all arable land unsuitable for high-value agriculture or silviculture might be used …

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Radiation Risk Predictions For Space Station Freedom Orbits, Francis A. Cucinotta, William Atwell, Mark Weyland, Alva C. Hardy, John W. Wilson, Lawrence W. Townsend, Judy L. Shinn, Robert Katz Jan 1991

Radiation Risk Predictions For Space Station Freedom Orbits, Francis A. Cucinotta, William Atwell, Mark Weyland, Alva C. Hardy, John W. Wilson, Lawrence W. Townsend, Judy L. Shinn, Robert Katz

Robert Katz Publications

Risk-assessment calculations are presented for the preliminary proposed solar minimum and solar maximum orbits for Space Station Freedom (SSF). Integral linear energy transfer (LET) fluence spectra are calculated for the trapped-proton and galactic cosmic ray (GCR) environments. Organ-dose calculations are discussed using the Computerized Anatomical Man model. The cellular track model of Katz is applied to calculate cell survival, transformation, and mutation rates for various aluminum shields. Comparisons between relative biological effectiveness (RBE) and quality factors (QF) for SSF orbits are made, and fluence-dependent effects are discussed.

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Additional Fossil Evidence On The Differentiation Of The Earliest Euprimates, Kenneth D. Rose, Thomas M. Bown Jan 1991

Additional Fossil Evidence On The Differentiation Of The Earliest Euprimates, Kenneth D. Rose, Thomas M. Bown

United States Geological Survey: Staff Publications

Several well-preserved jaws of the rare North American omomyid primate Steinius vespertinus, including the first known antemolar dentitions, have been discovered in 1989 and 1990 in the early Eocene Willwood Formation of the Bighorn Basin, Wyoming. They indicate that its dental formula is as primitive as those in early Eocene Donrussellia (Adapidae) and Teilhardina (Omomyidae) - widely considered to be the most primitive known euprimates - and that in various dental characters Steinius is as primitive or more so than Teilhardina. Therefore, despite its occurrence at least 2 million years later than Teilhardina, S. vespertinus is the …

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