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Spring 1990, Nsu Oceanographic Center Jan 1990

Spring 1990, Nsu Oceanographic Center

Currents

No abstract provided.


Summer 1990, Nsu Oceanographic Center Jan 1990

Summer 1990, Nsu Oceanographic Center

Currents

No abstract provided.


Fall 1990, Nsu Oceanographic Center Jan 1990

Fall 1990, Nsu Oceanographic Center

Currents

No abstract provided.


Changes In A Prairie Bird Population From 1940 To 1989, Neil P. Bernstein, Kristine K. Baker, Sherry R. Wilmot Jan 1990

Changes In A Prairie Bird Population From 1940 To 1989, Neil P. Bernstein, Kristine K. Baker, Sherry R. Wilmot

Journal of the Iowa Academy of Science: JIAS

We repeated a bird census of a prairie/field community that was done by Kendeigh (1941) in 1940. Changes in the bird populations were compared with changes in vegetation, agricultural land use for the county, and trends in urbanization. Grassland birds did decline in abundance due to causes similar to those cited in other studies. The increase in forest and edge nesting species was more unusual to this study, and probably correlated with the woody succession that had occurred.


Extinction Is Forever, Robert Loftin Ph.D, David Wallace Jan 1990

Extinction Is Forever, Robert Loftin Ph.D, David Wallace

Environmental Education Resources

Edited by Joan Bray and Teri Rosen. Research by La Tanya McNeal.

This booklet is an overview of the ice ages, extirpated Animals, extinct animals, endangered animals, and humans as an endangered species. In addition, it explores the impact that humans have on the environment and the problems with climate change.


Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer Jan 1990

Biological Activity And Conformational Analysis Of Nikkomycins And Their Analogs, Eduardo Krainer

Dissertations, Theses, and Capstone Projects

Nikkomycins and polyoxins are peptidyl nucleoside antibiotics produced by Streptomyces species. They are potent inhibitors of chitin synthetases from pathogenic fungi, and polyoxins have been used in Japan for many years as agricultural fungicides and for insect control. Since chitin synthetase is not found in mammals and both families of antibiotics are not toxic, these inhibitors are potentially attractive for clinical use. Unfortunately these compounds seem to have only a fungistatic action, and they are not used clinically at present.

A procedure for efficiently obtaining nikkomycins X and Z of very high purity from crude antibiotic is described. These nikkomycins …


Ectoparasites Of Ring-Necked Pheasants In Nebraska, William R. Payne, David W. Oates, Glen E. Dappen Jan 1990

Ectoparasites Of Ring-Necked Pheasants In Nebraska, William R. Payne, David W. Oates, Glen E. Dappen

Nebraska Game and Parks Commission: Staff Research Publications

In 1971, 1983 and 1984, ectoparasites were identified on 61 ring-necked pheasants (Phasianus colchicus) from Nebraska. Birds were collected throughout the state from 11 of 93 counties. Four species of chewing lice (Mallophaga) were collected: Lipeurus maculosus, Goniodes colchici, Lagopoecus coichicus and Amyrsidea megalosoma. One species of analgid mite, Megninia sp. was collected. Apparently, this species is new and undescribed. The four mallophagan species have not been reported from Nebraska.


Water Current, Volume 22, January 1990 Jan 1990

Water Current, Volume 22, January 1990

Water Current Newsletter

Gold Accepts Position at Texas A&M University
Platte River Policy
Congresswoman Smith Receives Water Statesman of the Year Award
Risks Not Always Easy to Measure
One Word or Two?
First Northeast Nebraska Water Quality Day Attracts 250 Persons
Who Wil Get the Water?
Water Qualty Priority of Nebraska Water Conference Council
Water Quality Outlook for the 90s Topic for Conference
Forum Addresses State Water Issues


Preserving Minnesota's Natural Heritage, Nelson T. French Jan 1990

Preserving Minnesota's Natural Heritage, Nelson T. French

Journal of the Minnesota Academy of Science

Minnesota has a rich natural resource base that can be preserved only by maintaining and expanding private and public conservation programs that contribute toward the protection of forests, soils, waters, native plants, wildlife, natural communities, and endangered species. Although efforts to protect Minnesota's natural heritage have been a model for the Midwest, increasing pressure to plow up prairie, drain wetlands, consume old growth forest resources, and urbanize the landscape continue to erode an ever decreasing base of natural habitat. Significant alteration of our state's presettlement biological communities has occurred and, in spite of conservation laws and rules adopted over the …


Nebraska Summary: S076 Case-Ih 5130, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S076 Case-Ih 5130, 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: S073 Massey Ferguson 362, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S073 Massey Ferguson 362, 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: S118 Ford Versatile 9030, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S118 Ford Versatile 9030, 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: S124 Massey Ferguson 3660, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S124 Massey Ferguson 3660, 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: S119 Ford Versatile 846, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S119 Ford Versatile 846, 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: S123 Massey Ferguson 3140, Nebraska Tractor Test Lab Jan 1990

Nebraska Summary: S123 Massey Ferguson 3140, 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 …


Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron Jan 1990

Analysis And Numerical Simulation Of The Ground Water System At The Bonneville Navigation Lock Site, Oregon, Dirk Baron

Dissertations and Theses

As part of the new navigation lock for Bonneville Dam a new water source for the Bonneville Fish Hatchery must be supplied. The hatchery is located on the Oregon side of the Columbia River downstream of the dam. It requires large quantities of water free from chemical and biological contamination. In addition, the water has to be in a narrow temperature range. Currently the fish hatchery receives its water from a well field that is located on the alluvial terrace downstream of Bonneville Dam. The well field lies in the proposed approach channel for the new lock and has to …


Glacial Deposits, Vol. 18, 1989-1990, Department Of Geography-Geology Jan 1990

Glacial Deposits, Vol. 18, 1989-1990, Department Of Geography-Geology

Glacial Deposits

Newsletter of the Department of Geography-Geology


Rheology Of Aqueous Suspensions Of Polystyrene Latex Stabilized By Grafted Poly(Ethylene Oxide), Harry J. Ploehn, J. W. Goodwin Jan 1990

Rheology Of Aqueous Suspensions Of Polystyrene Latex Stabilized By Grafted Poly(Ethylene Oxide), Harry J. Ploehn, J. W. Goodwin

Faculty Publications

A water-soluble carbodiimide has been used to end-graft aminated poly (ethylene oxide)(PEO) chemically onto colloidal polystyrene particles. Two particle sizes (115 and 347 nm diameter) and two PEO molecular weights (112 000 and 615 000 g mol–1) were combined to give suspensions with four different ratios of polymer layer thickness to particle radius. Electrophoresis demonstrated that the PEO was grafted, not just adsorbed. Dynamic light scattering showed that the adsorbed and grafted layers had similar structures and that non-ionic surfactant perturbed the PEO configurations. Steady shear and oscillatory rheometry indicated that long-ranged polymeric forces between particles governed the …


Principles And Clinical Applications Of Magnetic Resonance, Rao P. Gullapalli, Teresa T. Evans, Roger M. Hawk Jan 1990

Principles And Clinical Applications Of Magnetic Resonance, Rao P. Gullapalli, Teresa T. Evans, Roger M. Hawk

Journal of the Arkansas Academy of Science

A review is presented which covers the basic theory of nuclear magnetic resonance (NMR) with regard to angular momentum, magnetic moments, and the classical mechanical description of the NMR experiment. Longitudinal (T,) and Transverse (T2) relaxation times are defined as well as the basic pulse sequences used for their measurement. In particular, the 180°-t-90° and the Hahn Spin Echo pulse sequences are described in detail. Basic Magnetic Resonance Imaging (MRI) theory is discussed with regard to slice selection, frequency encoding, and phase encoding to define the imaged volume element. The equations defining the amount of Tt , T2 , and …


Impact Of Microprocessor Protected Mode Programming On Undergraduate Education N Engineering Technology, Robert L. Douglas Jan 1990

Impact Of Microprocessor Protected Mode Programming On Undergraduate Education N Engineering Technology, Robert L. Douglas

Journal of the Arkansas Academy of Science

No abstract provided.


Insecticides Based On Differences In Metabolic Pathways, Richard T. Mayer, G N. Cunningham, John T. Gupton Jan 1990

Insecticides Based On Differences In Metabolic Pathways, Richard T. Mayer, G N. Cunningham, John T. Gupton

Chemistry Faculty Publications

Insects have been major pests of humankind at least since the beginning of recorded history. To this day insects continue to cause problems in domestic, agricultural, and health situations. It is no wonder that people have continually sought new solutions to controlling insect pests. Even when new control methods are discovered and established, insects evolve into resistant species so that the method is only of real value for a few brief years. Modern science and technology are now enabling scientists to tear away the fabric that has so long masked physiological and biochemical events critical to insects. Armed with this …


Bulletin No 4168 - Plants In Australia Which When Eaten Produce Photosensitization In Livestock, T E H Aplin Jan 1990

Bulletin No 4168 - Plants In Australia Which When Eaten Produce Photosensitization In Livestock, T E H Aplin

Bulletins 4000 -

Photosensitization is the term used to describe inflammation of the skin (usually unpigmented) caused by photodynamic compounds, circulating in blood stream, becoming bound to dermal cells and fluorescing when the animal is exposed to ultraviolet light (290-400 nm).

Photosensitization usually occurs when an animal eats certain plants that contain photodynamic compounds. These compounds can be deposited unchanged in the skin after ingestion, the normal liver being incapable of excreting the native fluorescent compound. This is termed type 1 photosensitization and the compounds involved are naphthodianthrone derivatives. Photodynamic compounds can also be produced through aberrant metabolism by the liver due to …


Notes On Venezuelan Conservation, Aldemaro Romero Jr. Jan 1990

Notes On Venezuelan Conservation, Aldemaro Romero Jr.

Publications and Research

No abstract provided.


Van Lier Sequences, Peter C. Fishburn, Fred S. Roberts, Helen M. Marcus-Roberts Jan 1990

Van Lier Sequences, Peter C. Fishburn, Fred S. Roberts, Helen M. Marcus-Roberts

Department of Mathematics Faculty Scholarship and Creative Works

We study two types of sequences of positive integers which arise from problems in the measurement of comparative judgements of probability. The first type consists of the Van Lier sequences, which are nondecreasing sequences x1, x2,...,xn of positive integers that start with two 1's and have the property that, whenever j


Coatings And Surface Modification By Methane Plasma Polymerization, Chung‐Peng ‐P Ho, H. Yasuda Jan 1990

Coatings And Surface Modification By Methane Plasma Polymerization, Chung‐Peng ‐P Ho, H. Yasuda

Chemistry Faculty Research & Creative Works

Polymers formed from plasma‐polymerized methane were employed to modify the surface properties of silicone rubber membrane. Polymers were evaluated based on the energy input parameter W/FM, where W is the discharge power, F is the monomer flow rate, and M is the molecular weight of the monomer. Dealing with the characteristics of plasma polymerization and the deposited polymer film, the effect of pumping rate on deposition rate and the coating thickness, surface energy, and gas permeabilities of methane‐plasma‐polymer‐coated silicone rubber membrane were investigated in three plasma regions. Because more reactive species are expelled at high pumping rates, the monomer‐deficient region …


Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf Jan 1990

Dementia In Stroke Survivors In The Stroke Data Bank Cohort: Prevalence, Incidence, Risk Factors, And Computed Tomographic Findings, Thomas K. Tatemichi, Mary A. Foulkes, J. P. Mohr, Jeffrey R. Hewitt, Daniel B. Hier, Thomas R. Price, Philip A. Wolf

Chemistry Faculty Research & Creative Works

We Determined the Prevalence of Dementia in 927 Patients with Acute Ischemic Stroke Aged ≥60 Years in the Stroke Data Bank Cohort based on the Examining Neurologist's Best Judgment Diagnostic Agreement among Examiners Was 68% (K=0.34). of 726 Testable Patients, 116 (16%) Were Demented. Prevalence of Dementia Was Related to Age But Not to Sex, Race, Handedness, Educational Level, or Employment Status Before the Stroke. Previous Stroke and Previous Myocardial Infarction Were Related to Prevalence of Dementia Although Hypertension, Diabetes Mellitus, Atrial Fibrillation, and Previous Use of Antithrombotic Drugs Were Not Prevalence of Dementia Was Most Frequent in Patients with …


Experimental And Theoretical Study Of The Electron Spectra In 66.7350-Kev/U C++He Collisions, L. H. Toburen, R. (Robert) D. Dubois, C. O. Reinhold, D. R. Schultz, Ronald E. Olson Jan 1990

Experimental And Theoretical Study Of The Electron Spectra In 66.7350-Kev/U C++He Collisions, L. H. Toburen, R. (Robert) D. Dubois, C. O. Reinhold, D. R. Schultz, Ronald E. Olson

Physics Faculty Research & Creative Works

Measurements of the differential and total cross sections for production of free electrons are reported for collisions of 66.7350-keV/u C+ ions with He. The experimental data are compared with theoretical calculations that include electron emission from both target and projectile using the classical-trajectory Monte Carlo method and the independent-electron approximation. Good agreement is observed between theory and experiment, and structures appearing in the electron spectra can be explained in terms of either, or both, target and projectile ionization. © 1990 The American Physical Society.


Ultrastructure Des Sensilles Cylindriques, Mécanorécepteurs D'Un Crustacé Mysidacé Souterrain, Yves Crouau Jan 1990

Ultrastructure Des Sensilles Cylindriques, Mécanorécepteurs D'Un Crustacé Mysidacé Souterrain, Yves Crouau

International Journal of Speleology

The ultrastructural features of a new chordotonal sensillum in a cavernicolous Mysidacea is described. That sensillum and the other mechanoreceptor sensilla of the same Mysidacea are compared. 9 + 0 cilia show ultrastructural features which previously allowed us to establish a hypothesis with respect to the mode of functioning of chordotonal sensilla. That sensillum shows a pore at the tip of its external receptor.


Secondary Sympatric Occurrence Of Sibling Species Of Subterranean Shrimps In The Karst, M. Cobolli Sbordoni, M. Mattoccia, G. La Rosa, E. De Matthaeis, V. Sbordoni Jan 1990

Secondary Sympatric Occurrence Of Sibling Species Of Subterranean Shrimps In The Karst, M. Cobolli Sbordoni, M. Mattoccia, G. La Rosa, E. De Matthaeis, V. Sbordoni

International Journal of Speleology

Allozyme variation at 32 gene loci was studied in cave dwelling shrimps of the genus Troglocaris (fam. Atyidae). Populations were collected from several caves and wells belonging to different drainage systems in the Karst areas of NE Italy. Results suggest the existence of two sympatric, genetically distinct, biological species (provisionally indicated as species A and B in the T. anophthalmus complex) in the samples collected at the Duino Well, Sagrado and Comarie caves (Nei’s `D= 0.209). Samples from Gradisca and Aurisina are represented by only one (A) or the other (B) of the two species, respectively. Two remaining eastern populations …


Two New Niphargus Species (Amphipoda) From Caves In Yugoslavia, Gordan Karaman, Boris Sket Jan 1990

Two New Niphargus Species (Amphipoda) From Caves In Yugoslavia, Gordan Karaman, Boris Sket

International Journal of Speleology

Niphargus numerus sp. n. from the Čavlinska pećina near Obrovac (Dalmatia) and N. factor sp. n. from Vjetrenica (Hercegovina) are described. Both new species from Yugoslav caves belong to the N. transitivus aggregate of species.