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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 …


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 …


Management Of The Ozark Big-Eared Bat, Plecotus Townsendii Ingens, In Arkansas, Michael J. Harvey, Sam W. Barkley Jan 1990

Management Of The Ozark Big-Eared Bat, Plecotus Townsendii Ingens, In Arkansas, Michael J. Harvey, Sam W. Barkley

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 …


Plantscan, Ted Lefroy, Fritz Droge Jan 1990

Plantscan, Ted Lefroy, Fritz Droge

Natural resources published reports

PLANTSCAN is a network of schools and landholders throughout the wheatbelt of Western Australia. It aims to speed up the process of testing plants for their suitability to this environment.

This kit contains seed of various trees and shrubs and notes on how to grow them, plant them out into a small plot and record their progress.

Schools and landholders throughout the wheatbelt who have purchased this kit become part of a research network aimed at selecting plants that will:

* overcome soil erosion;

* overcome soil salinity;

* and provide a source of income for farmers.

The following sheets …


Competition Between Dipodomys And Perognathus In The Anza Borrego Desert State Park, Jodi Dorsey Jan 1990

Competition Between Dipodomys And Perognathus In The Anza Borrego Desert State Park, Jodi Dorsey

Whittier Scholars Program

The purpose of this experiment was to discover if competition for food and space existed between kangaroo rats and pocket mice. On three separate occasions, over eighty traps were set in a region of the Sonoran Desert near Anza Borrego Desert State Park. A total of seventy-eight kangaroo rats were caught, but not a single pocket mouse. There is no conclusion drawn about whether or not competition occurs between the two species. The project explains how each species has adapted to the harsh desert environment, and outlines suggested changes for a future experiment.


Salinity And Waterlogging On The Esperance Downs Research Station, D J. Mcfarlane, A T. Ryder Jan 1990

Salinity And Waterlogging On The Esperance Downs Research Station, D J. Mcfarlane, A T. Ryder

Resource management technical reports

Details the situation on the station so that the demonstration and research programs can be designed and the effect of the treatments assessed. Past work on the station has been briefly summarised and the results of geophysical surveys and additional drilling are given. Surveys of electromagnetic terrain conductivities have shown where salinity is most serious at present. The most deeply penetrating method may have identified areas likely to developing salinity in future.


Performance Improvements For Fddi And Csma/Cd Protocols, David Earl Game Jan 1990

Performance Improvements For Fddi And Csma/Cd Protocols, David Earl Game

Computer Science Theses & Dissertations

The High-Performance Computing Initiative from the White House Office of Science and Technology Policy has defined 20 major challenges in science and engineering which are dependent on the solutions to a number of high-performance computing problems. One of the major areas of focus of this initiative is the development of gigabit rate networks to be used in environments such as the space station or a National Research and Educational Network (NREN).

The strategy here is to use existing network designs as building blocks for achieving higher rates, with the ultimate goal being a gigabit rate network. Two strategies which contribute …


The Effects Of Variable Parameters On The Behavior Of Initial Wind Waves, Glen Harvey Wheless Jan 1990

The Effects Of Variable Parameters On The Behavior Of Initial Wind Waves, Glen Harvey Wheless

OES Theses and Dissertations

The generation mechanism of short wind waves is generally thought to be a viscous instability at the air-sea interface. The short, regular waves arising from a sudden wind on a still water surface have a dispersion relation which is characteristic of gravity-capillary waves. The effects of variable surface tension, viscosity and shear flow parameters on the behavior of these waves were studied.

A numerical hydrodynamic stability analysis of a coupled laminar shear flow was accomplished by integrating a transformed version of the Orr-Sommerfeld equation, subject to the boundary conditions at a two-fluid interface. Unbounded growth problems usually encountered in a …


Laboratory Studies Of Predatory Behaviour In Two Subspecies Of The Carabid Cave Beetle: Neaphaenops Tellkampfi, David M. Griffith Jan 1990

Laboratory Studies Of Predatory Behaviour In Two Subspecies Of The Carabid Cave Beetle: Neaphaenops Tellkampfi, David M. Griffith

International Journal of Speleology

Comparative studies on the foraging behaviour of Neaphaenops tellkampfi tellkampfi and N. t. meridionalis demonstrated adaptation to different environments. The southern subspecies N. t. meridionalis, which is found in wet muddy caves where cave cricket eggs are unlikely prey, did not locate buried cricket eggs and dug fewer and less accurate holes in the lab than the nominate subspecies. N. t. tellkampfi, which reaches high densities in sandy deep cave environments where cricket eggs are the only viable prey, gained significantly greater weight than meridionalis when presented buried cricket eggs as prey. There was no difference with respect …


Troglobius Coprophagus, A New Genus And Species Of Cave Collembola From Madagascar, With Notes On Its Ecology, José G. Palacios-Vargas, Jane Wilson Jan 1990

Troglobius Coprophagus, A New Genus And Species Of Cave Collembola From Madagascar, With Notes On Its Ecology, José G. Palacios-Vargas, Jane Wilson

International Journal of Speleology

Troglobius coprophagus n. g., n. sp. a cave Collembola from Madagascar is characterized by an elongate and serrate mucro, a non spines dens. Description and illustrations of the new genus and species are given. Some ecological data of this highly cave adapted species is also included.


Spacing Water Points In The Southern Pastoral Areas Of Western Australia, Don Burnside, Adrian Williams, Peter Curry Jan 1990

Spacing Water Points In The Southern Pastoral Areas Of Western Australia, Don Burnside, Adrian Williams, Peter Curry

Bulletins 4000 -

An inadequate distribution of watering points in our pastoral lands, particularly in the saltbush/bluebush pasture, has caused localisized land degradation close to waters and reduced animal productivity (particularly in stressful times). From experimentation and observation, some generalised recommendations for water supply distribution in pastoral areas can be made.


Development And Management Of Cattle Pastures In The High Rainfall Zone., Tony Albertsen Jan 1990

Development And Management Of Cattle Pastures In The High Rainfall Zone., Tony Albertsen

Experimental Summaries - Plant Research

Trial 87V8

Development and management of cattle pastures in the high rainfall zone.

To compare the effect of pasture species, pasture management and grazing management on pasture quantity, quality and cattle production.

Phalaris evaluation

In 1989 ninety three lines of Phalaris agrundinacea backcross with P. aquatica, bred by Dr. R.N. Oram (CSIRO Canberra) were drilled sown into unreplicated 10m single row plots at Vasse Research Station. In addition 7 controls (with two replications) were planted. Similar trials were planted by Mr. L. Cransberg (Albany) and Dr. R.N. Oram (Bendigo).

Evaluation of annual and short term rotation ryegrass.

The increasing range …


Estimates Of Spawning Stock Size Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay, 1986-1987, Cynthia M. Jones, John R. Mcconaugha, Patrick J. Geer, Michael H. Prager Jan 1990

Estimates Of Spawning Stock Size Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay, 1986-1987, Cynthia M. Jones, John R. Mcconaugha, Patrick J. Geer, Michael H. Prager

OES Faculty Publications

The 1986 spawning stock exhibited a single abundance peak, increasing from 1.0×105 individuals in early July to 9.3×106 in late July, maintaining high levels throughout the summer, and declining in the fall to 7.4×105 individuals. The 1987 spawning stock showed 2 peaks of abundance. The population reached the lesser peak, 1.0×106 individuals, in late July; the greater peak, 1.5×106, in late August. By late September, the population had declined to 6.5×105 individuals. The peak abundance of the 1987 female spawning stock was only 16% as great as the peak abundance in 1986; the 1987 spawning stock size in 1986. Variability …


Fecundity Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay: Biological, Statistical And Management Considerations, Michael H. Prager, John R. Mcconaugha, Cynthia M. Jones, Patrick J. Geer Jan 1990

Fecundity Of Blue Crab, Callinectes Sapidus, In Chesapeake Bay: Biological, Statistical And Management Considerations, Michael H. Prager, John R. Mcconaugha, Cynthia M. Jones, Patrick J. Geer

OES Faculty Publications

Ovigerous blue crabs were collected from the mouth of Chesapeake Bay during the 1986 and 1987 spawning seasons. Mean carapace width was 14.7 cm; mean fecundity was 3.2×106 eggs. Fecundity was significantly related to carapace width, and did not vary significantly with developmental stage of the eggs. Mean fecundities were 2.6×106 eggs in 1986, and 4.0×106 eggs in 1987. An additive model with year and size effects described the observed fecundities reasonably well, was compact, and was easier to interpret than a multiplicative model. To fit a more general model without year effects, the authors took the mean of 1986 …


Caudate Infarcts, Louis R. Caplan, Edward Feldmann, Jeremy D. Schmahmann, Carlos S. Kase, Phillip B. Gorelick, Daniel B. Hier, Cathy Helgason, George Baquis, John P. Greenberg Jan 1990

Caudate Infarcts, Louis R. Caplan, Edward Feldmann, Jeremy D. Schmahmann, Carlos S. Kase, Phillip B. Gorelick, Daniel B. Hier, Cathy Helgason, George Baquis, John P. Greenberg

Chemistry Faculty Research & Creative Works

Eighteen Patients Had Caudate Nucleus Infarcts (10 Left-Sided; 8 Right-Sided). Infarcts Extended into the Anterior Limb of the Internal Capsule in 9 Patients, and Also the Anterior Putamen in 5 Patients. Thirteen Patients Had Motor Signs, Most Often a Slight Transient Hemiparesis. Dysarthria Was Common (11 Patients). Cognitive and Behavioral Abnormalities Were Frequent, and Included Abulia (10 Patients), Agitation and Hyperactivity (7 Patients), Contralateral Neglect (3 Patients, All Right Caudate), and Language Abnormalities (2 Patients, Both Left Caudate). the Majority of Patients Had Risk Factors for Penetrating Artery Disease. Branch Occlusion of Heubner's Artery, or Perforators from the Proximal Anterior …


Undergraduate Elementary Education Students’ Concepts Of Light, Deborah Lynn Orr Jan 1990

Undergraduate Elementary Education Students’ Concepts Of Light, Deborah Lynn Orr

Dissertations and Theses @ UNI

The purpose of the study was to describe some ideas that future elementary school teachers have about light and shadows. Twenty-five freshmen and sophomores in elementary education were interviewed using the Interview-About-Instances technique developed by Osborne and Gilbert. Students were asked to explain specific instances of sources and non-sources of light, the distance light travels, and the role of light in vision. Students defined the word "shadow" and predicted where shadows could be in particular situations. The results of this study indicate that many students lack factual information or have misconceptions concerning light propagation. Fifty-six percent of the students in …


Neogastropods (Melongenidae, Fasciolariidae, Turridae) From The Cannonball Formation (Paleocene: Thanetian), North Dakota And South Dakota, Brian E. Silfer Jan 1990

Neogastropods (Melongenidae, Fasciolariidae, Turridae) From The Cannonball Formation (Paleocene: Thanetian), North Dakota And South Dakota, Brian E. Silfer

Theses and Dissertations

The Cannonball Formation of Paleocene age is a shallow-marine, clastic sequence exposed primarily in southwest-central North Dakota and northwestern South Dakota. The formation is characterized by alternating, poorly consolidated, relatively thin sandstone and thick mudstone units. The Cannonball neogastropod families Melongenidae, Fasciolariidae, and Turridae contain 20 species assigned to 15 genera based on 334 individuals from 50 localities. Four genera, Alticollarum, Obtusicarina, Vitticoncha, and Ericksonia are new, whereas Serrifusus, Mesorhytis, Rhombopsis, and Deussenia are first reported occurrences from Tertiary strata. Marshallaria is newly reported from North America and likely from the Northern Hemisphere. Twelve species are additions to the Cannonball …


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 …


Isopoda (Crustacea: Isopoda: Microcharon, Jaera, Proasellus) And Other Fauna In Hypogean Waters Of Southern Cyprus, Boris Sket Jan 1990

Isopoda (Crustacea: Isopoda: Microcharon, Jaera, Proasellus) And Other Fauna In Hypogean Waters Of Southern Cyprus, Boris Sket

International Journal of Speleology

Springs and wells in SW and S part of Cyprus were briefly surveyed. Chlorinity was 0.1 - 0.8 p.p.t. Some isopods were found in collecting galleries of springs and in wells in calcarenites and in gravel deposits. These were Proasellus coxalis ssp. with some depigmented specimens, the probably stygobitic P. c. nanus ssp. n., poorly pigmented Jaera italica, and Microcharon luciae n. sp.; they were accompanied by the stygobitic amphipod Bogidiella cypria, by Turbellaria (Tricladida), by Copepoda (Cyclopoida), and rarely by some other animals (Pisidium sp., Oligochaeta). Only slightly depigmented Turbellaria Tricladida (cf. Dugesia sp.) occur in …


Using Water Naturally, Holmes Rolston, Iii, University Of Colorado Boulder. Natural Resources Law Center Jan 1990

Using Water Naturally, Holmes Rolston, Iii, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

[ii], 26 p. ; 28 cm


An Outline Of China's Natural Resources Law, Gu Xueting, University Of Colorado Boulder. Natural Resources Law Center Jan 1990

An Outline Of China's Natural Resources Law, Gu Xueting, University Of Colorado Boulder. Natural Resources Law Center

Books, Reports, and Studies

8 p. ; 28 cm


The Development Of An Expert System For The Diagnosis Of Diseases In Fibre And Dairy Goats, Tim S. Roberts Jan 1990

The Development Of An Expert System For The Diagnosis Of Diseases In Fibre And Dairy Goats, Tim S. Roberts

Theses: Doctorates and Masters

This thesis details the development of an expert system for the diagnosis of diseases in fibre and dairy goats. Divided into five sections, five appendices, and a bibliography, this thesis centres on the methods used to build the expert system: the decisions taken at the outset of, and during the course of, development; some of the problems encountered, and the solutions to those problems. A detailed appraisal is made of the development process and suggestions are made for future developments over similar domains (for example, the diagnosis of diseases in animals other than goats). Much emphasis is placed on three …


Aqueous Absorption Of Nox Induced By Sodium Chlorite Oxidation, Chen-Lu Yang Dec 1989

Aqueous Absorption Of Nox Induced By Sodium Chlorite Oxidation, Chen-Lu Yang

Theses

Aqueous scrubbing in alkaline media for the removal of nitrogen oxides (NOx) from flue gases using NaClO2 as an oxidant is being investigated in the Chemical Engineering Department of New Jersey Institute of Technology. This thesis presents the findings of an experimental program that was conducted to estimate the capability of NaClO2 aqueous solution to oxidize insoluble NO to soluble NO2 in order to increase its solubility and thus prevent NOx emission from entering the atmosphere from flue gases emitted by municipal incinerators or power plants.

The key findings of this program are:

* …


Fisheries Research Report No 85 - A Description Of The British United Trawlers/Southern Ocean Trawlers Operation In The Great Australian Bight During The Period 19.11.77 To 28.5.79, M. H. Walker, S. J. Blight, D. P. Clarke Dec 1989

Fisheries Research Report No 85 - A Description Of The British United Trawlers/Southern Ocean Trawlers Operation In The Great Australian Bight During The Period 19.11.77 To 28.5.79, M. H. Walker, S. J. Blight, D. P. Clarke

Fisheries Research Reports

This report documents the operations of three British United Trawlers/Southern Ocean Trawlers freezer stern trawlers in the Great Australian Bight for the period 19.11.77 to 28.5.79. During this period the trawlers conducted 20 fishing trips utilising demersal and pelagic trawling. A description and brief resume of these fishing operations is provided. The trawlers' vessel and gear specifications and fishing and processing operations are also described. The report provides background to Fisheries Research Report 86, which documents the demersal catches made during the trawler operations.


Education Is For The Students' Future, Hassler Whitney Dec 1989

Education Is For The Students' Future, Hassler Whitney

Humanistic Mathematics Network Journal

No abstract provided.


Fisheries Research Report No 86 - The Demersal Trawl Resources Of The Great Australian Bight As Indicated By The Fishing Operations Of The Stern Trawlers Othello, Orsino And Cassio In The Period 19.11.77 To 28.5.79, M. H. Walker, D. P. Clarke Dec 1989

Fisheries Research Report No 86 - The Demersal Trawl Resources Of The Great Australian Bight As Indicated By The Fishing Operations Of The Stern Trawlers Othello, Orsino And Cassio In The Period 19.11.77 To 28.5.79, M. H. Walker, D. P. Clarke

Fisheries Research Reports

A joint fishing venture between a Western Australian company, Southern Ocean Fish Processors, and a United Kingdom company, British United Trawlers, operated three large Othello class stern trawlers in the Great Australian Bight in the period 19.11.77 to 28.5.79. This report documents the catch and effort data collected from the vessels’ demersal trawling activities. Descriptions of gear and fishing operations are provided in Fisheries Research Report 85, 1989. The three trawlers made a total of 20 trips to Great Australian Bight waters. A daily trawling log was kept for each trip, recording position and time of trawls, net type, and …


The Probe, Issue 98 - December 1989 Dec 1989

The Probe, Issue 98 - December 1989

The Probe: Newsletter of the National Animal Damage Control Association

THE PROBE National Animal Damage Control Association
DECEMBER 1989
Vote
NADCA Elections
NADCA Annual Meeting
Letters to Ye Ed
APHIS Activity Report
Animal Rights


The Prairie Naturalist Volume 21, No.4 December 1989 Dec 1989

The Prairie Naturalist Volume 21, No.4 December 1989

The Prairie Naturalist

SMALL MAMMALS IN TALL-GRASS PRAIRIE: PATTERNS ASSOCIATED WITH GRAZING AND BURNING ▪ E. K. Clark, D. W. Kaufman, E. J. Finck, and G. A. Kaufman

BURROW DISTRIBUTION OF THIRTEEN-LINED GROUND SQUIRRELS IN RELATION TO TREE CANOPIES ▪ J. L. Koprowski 185

SPRING AND SUMMER PREY REMAINS COLLECTED FROM MALE MINK DENS IN SOUTHWESTERN MANITOBA ▪ . T. W. Arnold and E. K. Fritzell

BREEDING CANVASBACKS: A TEST OF A HABITAT MODEL ▪ D. H. Johnson, M. C. Hammond, T. L. McDonald, C. L. Nustad, and M. D. Schwartz

A CHECKLIST OF THE ANTS OF OKLAHOMA ▪ G. C. Wheeler and …