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A Vertebrate Survey Of Kasota Prairie, Kenneth Hessenius Jan 1982

A Vertebrate Survey Of Kasota Prairie, Kenneth Hessenius

Journal of the Minnesota Academy of Science

Kasota Prairie is a 30-acre tract of near-virgin prairie in Le Seur County, Minnesota. The vertebrate population at the prairie was studied to determine its significance as habitat for those species. Several species of birds which require prairie or prairie-like habitat were found to be nesting there. Many other avian species also utilize the area for feeding purposes. Small mammal populations were highly influenced by annual prairie maintenance burning.


Introduced Annual Eriogonum In Minnesota, Charles L. Argue, Steven R. Argue Jan 1982

Introduced Annual Eriogonum In Minnesota, Charles L. Argue, Steven R. Argue

Journal of the Minnesota Academy of Science

A selected summary of the utility of data derived from the recording and analysis of immigrant plant species is considered in relation to an apparently Introduced Minnesota population of Eriogonum annuum Nutt., the Annual Eriogonum. Fruiting specimens and one flowering-specimen of this species, heretofore reported on xeric sites from the western Dakotas, Montana, and Wyoming south into Mexico, were collected October 13, 1982, on the Sherburne National Wildlife Refuge near Zimmerman, Minnesota, and represent the first records of an Eriogonum in this state.


Utilization Of Wood Duck Nest Boxes By Wildlife Near Cohasset, Minnesota, Robert T. Bohm Jan 1982

Utilization Of Wood Duck Nest Boxes By Wildlife Near Cohasset, Minnesota, Robert T. Bohm

Journal of the Minnesota Academy of Science

Twenty-seven wood duck boxes located along the Mississippi River near Cohasset, Minnesota were monitored for winter and spring wildlife use from 198o-1982. During these three yearn, overall nest box use was 84 percent, 72 percent, and 82 percent, respectively; winter utilization was 44 percent, 56 percent, and 68 percent; spring utilization was 48 percent, 44 percent, and 37 percent. Most winter use was by red squirrels, gray squirrels, and starlings. Principal spring use was by wood ducks and common goldeneyes, During the course of the study, wood duck use decreased and common goldeneye use Increased. Aspects of the nesting season …


Protein Bodies In Dormant, Imbibed And Germinated Sunflower Cotyledons, R. D. Allen, H. J. Arnott Jan 1982

Protein Bodies In Dormant, Imbibed And Germinated Sunflower Cotyledons, R. D. Allen, H. J. Arnott

Food Structure

Scanning electron microscopy was used to observe the morphology and structure of protein bodies in dormant and imbibed sunflower cotyledons and to document the morphological changes in protein bodies during germination and seedling growth. In order to clearly visualize dormant seed structure, anhydrous fixation techniques were employed. Definite differences in cellular structure are seen in comparisons of dry and imbibed seed tissues. As germination proceeds, protein bodies lose their smooth spherical shape and become indented and pitted. Protein body coalescence and fusion precedes the formation of a central protein vacuole. As protein is hydrolyzed, protein vacuole density decreases, and its …


Viruses Of Symbiotic Chlorella-Like Algae Isolated From Paramecium Bursaria And Hydra Viridis, James L. Van Etten, Russel H. Meints, Daniel Kuczmarski, Dwight E. Burbank, Kit Lee Jan 1982

Viruses Of Symbiotic Chlorella-Like Algae Isolated From Paramecium Bursaria And Hydra Viridis, James L. Van Etten, Russel H. Meints, Daniel Kuczmarski, Dwight E. Burbank, Kit Lee

Department of Plant Pathology: Faculty Publications

We previously reported that isolation of symbiotic Chloreila-like algae from the Florida strain of Hydra viridis induced replication of a virus (designated HVCV-1) in the algae. We now report that isolation ofsymbiotic Chlorella-like algae from four other sources of green hydra and one source ofthe protozoan Paramecium bursaria also induced virus synthesis. Algae from one of these hydra contained a virus identical to HVCV-1 (based on its rate of sedimentation, buoyant density, reaction to HVCV-1 antiserum, and DNA restriction fragments) whereas algae from the other three hydra contained. another similar, but distinct, virus (designated HVCV-2). The virus from the paramecium …


Grain Structure And End-Use Properties, Y. Pomeranz Jan 1982

Grain Structure And End-Use Properties, Y. Pomeranz

Food Structure

Practical implications of grain structure relate to every step from grain development and production through market ing to processing, utilization, and consumption . The structure and adherence of the hulls may contribute to protection of grain during germination or malting and protection against insect infestations . Germ retention during threshing and separation during processing depend on the germ structure and location in the kernel. The subaleurone and central endosperm layers differ in cell size, shape, and structure and in composition, especially with regard to protein contents and quality. The main factors in grain hardness are the intrinsic hardness of the …


A Transport Equation Theory Of Electron Scattering, D. J. Fathers, P. Rez Jan 1982

A Transport Equation Theory Of Electron Scattering, D. J. Fathers, P. Rez

Scanning Electron Microscopy

The use of the Boltzmann transport equation to describe electron scattering in electron microscopy and electron probe microanalysis is discussed. A method of solution is given in which the transport equation is divided into angle and energy intervals. This gives rise to a number of coupled first order differential equations. Separation into forward and backward travelling components of the electron flux distribution enables the correct boundary conditions to be imposed. Solutions are derived which take the form of matrix operators analytic in both depth and target thickness. These matrices allow derivation of other physical quantities such as X-ray or Auger …


Electron Microscopy Of Milk And Milk Products: Problems And Possibilities, D. G. Schmidt Jan 1982

Electron Microscopy Of Milk And Milk Products: Problems And Possibilities, D. G. Schmidt

Food Structure

Milk and dairy products have frequently been studied by transmission- and scanning electron microscopy. The specimen preparation procedure may considerably influence the final result, and formation of artefacts is frequently observed. In this respect, formation of ice crystals during cryofixation is a well-known phenomenon. But dehydration, to an extent such as is required for embedding procedures, also appears to be harmful to dairy products. Micrographs of thin sections of plastic- embedded samples of casein submicelles show threadlike material, whereas in freeze-etched specimens only spherical particles are found. Similar observations are made when samples of cheese and of concentrated milk are …


Fluorescence Microscopy Of Cereals, R. G. Fulcher Jan 1982

Fluorescence Microscopy Of Cereals, R. G. Fulcher

Food Structure

The fluorescence microscope is one of the most sensitive instruments available for morphological and microchemical analysis of biological material, and especially of cereal grains. Recent innovations in illuminating systems, fluorescence chemistry, and specimen preparation have combined to provide significant improvements over conventional bright-field microscopy in both specificity and sensitivity. A variety of relatively specific fluorescent markers has been devised for routine and high resolution detection of all major cereal components. Several examples of useful fluorescent markers are described, including appropriate methods for specimen preparation, fluorescence analysis, and photography.


Monte Carlo Calculations On The Spatial And Angular Distributions Of High Energy Electron Beams In Amorphous And Polycrystalline Films, J. L. Balladore, J. P. Martinez, J. Trinquier, B. Jouffrey Jan 1982

Monte Carlo Calculations On The Spatial And Angular Distributions Of High Energy Electron Beams In Amorphous And Polycrystalline Films, J. L. Balladore, J. P. Martinez, J. Trinquier, B. Jouffrey

Scanning Electron Microscopy

We study the plural scattering of electrons in amorphous and polycrystalline films. The incident electron energy ranges from 0.1 to 3 MeV. The cross sections are obtained by measuring the transmission coefficient for targets of gold, silver, aluminium and carbon. The partial elastic cross section is calculated from Lenz's theory using a Wentzel-Yukawa model for the atomic potential of the scattering atom. In the case of inelastic interactions, we take into account either scattering by a free atom (Morse's approximation) or scattering by plasmon creation (relativistic theory of Ashley Ritchie). From these results, we solve the problem of electron transport …


The Role Of The Background In Auger Electron Spectroscopy, H. E. Bishop Jan 1982

The Role Of The Background In Auger Electron Spectroscopy, H. E. Bishop

Scanning Electron Microscopy

In Auger Electron Spectroscopy (AES) the characteristic Auger peaks are superimposed on a relatively high continuum of back-scattered electrons. In the commonly used differential mode of recording Auger spectra, the influence of the background appears through its contribution to the noise and the enhancement of the Auger signal that makes a backscattering correction necessary in quantitative AES. With the increased use of low incident beam currents to achieve high spatial resolution, the direct spectrum is increasingly used, so that a better understanding of the background is desirable. In this paper the variations of the background with atomic number, incident beam …


Monte Carlo Simulation Of Electron Scattering In Resist Film/Substrate Targets, Kenji Murata Jan 1982

Monte Carlo Simulation Of Electron Scattering In Resist Film/Substrate Targets, Kenji Murata

Scanning Electron Microscopy

First the fundamentals of resist modelling required to implement an analysis of developed resist patterns were studied, which represents the relationship between the energy deposited by incident electrons and the solubility characteristics of a positive or negative resist. Next, two models of single elastic scattering and fast secondary (knock-on) electron production were studied for Monte Carlo simulation of electron scattering in resist film/substrate targets, and the statistical errors of Monte Carlo results were evaluated. Finally, problems in electron beam lithography were investigated with the simulation. The exposure intensity distribution was studied with the two models. A comparison between Monte Carlo …


Food Microstructure: An Integrative Approach, E. A. Davis, J. Gordon Jan 1982

Food Microstructure: An Integrative Approach, E. A. Davis, J. Gordon

Food Structure

The integration of information at all levels of organization in a food system - atomic and molecular through macroscopic properties is illustrated with cake batters as an example of a formulated food and bovine muscle as an example of a biologically intact, non-formulated food. Direct examples are given using macroscopic data collected in heat and water transport studies followed by integration of microscopical data for interpretive purposes.

The contribution of starch gelatinization to the characteristics of water loss in batter is related to events such as loss of brief ringence as seen by polarizing microscopy , differential heat input as …


Characterization Of Breeds Representing Diverse Biological Types: Postweaning Growth And Feed Efficiency, Larry V. Cundiff, Robert M. Koch, Keith E. Gregory Jan 1982

Characterization Of Breeds Representing Diverse Biological Types: Postweaning Growth And Feed Efficiency, Larry V. Cundiff, Robert M. Koch, Keith E. Gregory

Roman L. Hruska U.S. Meat Animal Research Center: Reports

On a life-cycle basis, about 30% of the energy requirements for beef production are consumed by steers and heifers during the period from weaning to slaughter. About 45 to 55% of the total feed costs are incurred in the postweaning period, depending on the cost of feed resources for the cow herd relative to those for the feedlot. We find it is important, therefore, to characterize breeds of cattle for rate and efficiency of postweaning gain.


Methane And Protein From Beef Cattle Manure, Andrew G. Hashimoto, Yud-Ren Chen, Vincent H. Varel, Ronald L. Prior Jan 1982

Methane And Protein From Beef Cattle Manure, Andrew G. Hashimoto, Yud-Ren Chen, Vincent H. Varel, Ronald L. Prior

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Dwindling supplies of conventional fossil fuels have prompted renewed interest in recovering energy through the bioconversion of waste organic materials. The large quantities of manure produced in confinement feedlots and the need to manage this manure effectively make feedlots a logical choice for assessing the feasibility of recovering methane and protein through anaerobic fermentation.

Research at U.S. Meat Animal Research Center is designed to determine the technical and economic feasibility of recovering methane and protein from beef cattle manure.

Specific Objectives are to:

1. Develop design criteria for optimum production of methane and protein through anaerobic fermentation of beef cattle …


Characterization Of Breeds Representing Diverse Biological Types: Postweaning Growth And Puberty Of Females, Keith E. Gregory, Larry V. Cundiff, Robert M. Koch Jan 1982

Characterization Of Breeds Representing Diverse Biological Types: Postweaning Growth And Puberty Of Females, Keith E. Gregory, Larry V. Cundiff, Robert M. Koch

Roman L. Hruska U.S. Meat Animal Research Center: Reports

Puberty traits in beef cattle are important criteria for evaluating the use of breeds for different beef production systems. Age at puberty is an important trait in beef cattle where females are bred to calve at 2 years of age, especially when a restricted breeding season is used. It is not only important that heifers reach puberty and conceive, but that they conceive early in the breeding season. Heifers that fail to reach puberty or that reach puberty and conceive late in the breeding season cause reduced production efficiency. Thus, from a breed selection standpoint, puberty is an important trait …


Characterization Of Breeds Representing Diverse Biological Types: Preweaning Traits, Keith E. Gregory, Larry V. Cundiff, Robert M. Koch Jan 1982

Characterization Of Breeds Representing Diverse Biological Types: Preweaning Traits, Keith E. Gregory, Larry V. Cundiff, Robert M. Koch

Roman L. Hruska U.S. Meat Animal Research Center: Reports

The germ plasm base for beef cattle production in the United States has been broadened considerably during the last decade, primarily as a result of the development of appropriate quarantine facilities and procedures by the Canada Department of Agriculture that have provided for importing several new breeds of European origin. Also, the importation of new breeds, along with other factors, has stimulated interest in increased use for beef production of several breeds that have been available in North America for many years. The newly introduced breeds added to the breeds already available in the United States provide a wide range …


Resource Management Thrusts And Opportunities: National Parks And Wildlife Refuges, G. Ray Arnett Jan 1982

Resource Management Thrusts And Opportunities: National Parks And Wildlife Refuges, G. Ray Arnett

United States Fish and Wildlife Service: Publications

Well, it's been an interesting year. Somehow, it got to be very convenient for some folks to misconstrue what the Secretary had said. Some of those folks just seemed determined to make James Watt a household name-and they succeeded. And those same folks succeeded, too, in increasing the membership roles of a few of the environmental groups. But I don't think they succeeded very well in listening to and understanding what the Secretary said a year ago .... So, as succinctly and plainly as possible, I will spell out again that the goals of this Administration weren't designed to create …


Effects Of Increased Human Populations On Wildlife Resources Of The Kenai Peninsula, Alaska, Edward E. Bangs, Ted H. Spraker, Theodore N. Bailey, Vernon D. Berns Jan 1982

Effects Of Increased Human Populations On Wildlife Resources Of The Kenai Peninsula, Alaska, Edward E. Bangs, Ted H. Spraker, Theodore N. Bailey, Vernon D. Berns

United States Fish and Wildlife Service: Publications

In this paper, we will discuss what has occurred to several wildlife populations on the Kenai Peninsula as the human population increased. By discussing historical impacts, management techniques, and potential human impacts, we intend to show the significance of what occurred and may occur as human populations expand, both on the Kenai and in Alaska.


Status Of Alaska Sea Otter Populations And Developing Conflicts With Fisheries, Ancel M. Johnson Jan 1982

Status Of Alaska Sea Otter Populations And Developing Conflicts With Fisheries, Ancel M. Johnson

United States Fish and Wildlife Service: Publications

Although sea otters (Enhydra lutris) have been a relatively insignificant resource in Alaska during the twentieth century, the situation is changing. Remnant populations that recolonized most of their historic range are becoming recognized as a potentially valuable economic resource and as a competitor with some important shellfish fisheries. It is appropriate that sea otters should again become an important Alaskan resource because they were so significant in the initial exploration and settlement of Alaska by non-natives. In this paper I review changes in distribution and population abundance since 1740, recent changes in human attitudes toward sea otters, and …


Hep As A Planning Tool: An Application To Waterfowl Enhancement, Scott C. Matulich, Jeffrey E. Hanson, Ivan Lines, Adrian Farmer Jan 1982

Hep As A Planning Tool: An Application To Waterfowl Enhancement, Scott C. Matulich, Jeffrey E. Hanson, Ivan Lines, Adrian Farmer

United States Fish and Wildlife Service: Publications

To many, the principal role of wildlife agencies in public and private resource development has been that of impact mitigation. With known or pending habitat damage, biologists have to develop mitigation or compensation plans. Unfortunately, once in a mitigation framework, they are in a no-win situation, seeking remedial action at best. Yet, the potential exists for cooperative project planning, thereby facilitating mitigation of impacts before they occur, and enhancement of environmental amenities through project development. In fact, such planning is mandated by federal legislation (e.g., National Environmental Policy Act, Fish and Wildlife Coordination Act, Outdoor Recreation Act, etc.).


Development And Use Of A Habitat Gradient Model To Evaluate Wildlife Habitat, Henry L. Short Jan 1982

Development And Use Of A Habitat Gradient Model To Evaluate Wildlife Habitat, Henry L. Short

United States Fish and Wildlife Service: Publications

Ecologists and wildlife managers are increasingly confronted with the problems of predicting the value of surface cover as wildlife habitat and developing management alternatives to offset wildlife values lost because of land-use change. These problems have become urgent and more acute because of increased demand for products from the land and diminished fiscal and manpower resources for obtaining meaningful environmental information for the decision maker. This paper describes a relatively rapid, simple, and quantitative process for evaluating the quality of an area as wildlife habitat.


Maps Of Distribution And Abundance Of Selected Species Of Birds On Uncultivated Native Upland Grasslands And Shrubsteppe In The Northern Great Plains, Harold A. Kantrud Jan 1982

Maps Of Distribution And Abundance Of Selected Species Of Birds On Uncultivated Native Upland Grasslands And Shrubsteppe In The Northern Great Plains, Harold A. Kantrud

United States Fish and Wildlife Service: Publications

Many areas of the northern Great Plains (Fenneman 1931) remain poorly known ornithologically. Knowledge of species distribution in portions of this vast area has been advanced by recent State birds books (Stewart 1975; South Dakota Ornithologists' Union 1978) but many voids remain. Especially desirable for biologists and land managers is information concerning the relative abundance of plant and animal species over large land areas. This information can only be obtained from extensive surveys of the biota. The field of community ecology has been severely hampered by lack of information on species abundance (Dice 1930; Cain 1947; Partch 1962; Udvardy 1963). …


Reproductive Biology Of Cheirostemon Platanoides (Sterculiaceae): I. Factors Influencing Nectar Properties, Ron Scogin Jan 1982

Reproductive Biology Of Cheirostemon Platanoides (Sterculiaceae): I. Factors Influencing Nectar Properties, Ron Scogin

Aliso: A Journal of Systematic and Floristic Botany

No abstract provided.


Report No 49 - Geographically Restricted Plants Of Southern Western Australia, Barbara L. Rye Jan 1982

Report No 49 - Geographically Restricted Plants Of Southern Western Australia, Barbara L. Rye

Fisheries Research Reports

This publication lists 527 angiosperm species native to southern western Australia whose known geographical ranges are less than 100 kilometres long. A further 128 angiosperms are listed with geographical ranges between 100 and 160 kilometres. No fern or gymnosperm species in the region are known to be geographically restricted.

Apart from the presently unnamed species, a large majority of the rare plants of southern Western Australia are believed to be listed, including 86 of the species that have been gazetted as rare flora.

Less than 40% of the listed species are known to occur on conservation reserves and less than …


Fishery Report No 55 - The Western Rock Lobster Fishery 1961 - 1971, G. R. Morgan, E H. Barker Jan 1982

Fishery Report No 55 - The Western Rock Lobster Fishery 1961 - 1971, G. R. Morgan, E H. Barker

Fisheries Research Reports

The fishery for the western rock lobster, Panulinus cygnus is one of the most important single fisheries in Australia and one of the major rock lobster fisheries of the world with catches in recent years averaging some 8000 tonnes annually. The history of the commercial fishery extends back to 1944/45 factory when a canning was opened at the Abrolhos Islands (Figure 1) with a view to supplying the Australian armed forces. After the World war, an export market for fresh frozen rock lobster tails was quickly established in the U.S.A. and the industry, sharing in the advantages of postwar reconstruction, …


Fisheries Report No 50 - Feasibility Trawling Activities In The Great Australian Bight By The Korean Trawlers Dong Ban 91 And Dong Won 509 During The Period 15.11.79 To 12.1.80, Michael H. Walker, Stuart J. Blight, Gerald M. Cliff Jan 1982

Fisheries Report No 50 - Feasibility Trawling Activities In The Great Australian Bight By The Korean Trawlers Dong Ban 91 And Dong Won 509 During The Period 15.11.79 To 12.1.80, Michael H. Walker, Stuart J. Blight, Gerald M. Cliff

Fisheries Research Reports

Four Korean fishing trawlers operated in Western Australian waters, largely on the Northwest shelf, during 1979 under State/Commonwealth feasibility fishing arrangements. Two of these vessels, Dong Bang 91 and Dong Won 509, were given permission by Government, late in 1979, to conduct demersal trawling operations in the Great Australian Bight between longitudes 116°£ to 138°E and outside of 12 miles from shore.

Two observers from the Western Australian Department of Fisheries and Wildlife were involved with monitoring the activities of these vessels at sea in the Bight.

This report describes the operations of these Korean vessels in detail and represents …


Fisheries Report No 51 - 'Taiyo Maru 71" Demersal Trawling Cruise In Western Australian Coastal Waters South Of 21 S, July-September, 1979, D. I. Heald, M. H. Walker Jan 1982

Fisheries Report No 51 - 'Taiyo Maru 71" Demersal Trawling Cruise In Western Australian Coastal Waters South Of 21 S, July-September, 1979, D. I. Heald, M. H. Walker

Fisheries Research Reports

A Japanese demersal trawler, 'Taiyo Maru 771' was given special permission to conduct exploratory trawling in the period 73.7.79-16.9.79 off the Western Australian coast between 21°S Latitude and 35°30'S Latitude, an area which partly overlapped the fishing grounds for the western rock Lobster. The vessel was required to complete a catch, fishing effort and species composition log book issued by the Commonweath Department of Primary Industry. Two Western Australian Department of Fisheries and Wildlife observers on board monitored fishing operations for the entire duration of the cause and undertook research.

Details of each trawl conducted are given and discussed. Catch …


New And Interesting Plants For The Arkansas Flora From Northeastern Arkansas, Edward Leon Richards Jan 1982

New And Interesting Plants For The Arkansas Flora From Northeastern Arkansas, Edward Leon Richards

Journal of the Arkansas Academy of Science

No abstract provided.


Band Pattern In Helix Aspersa: Variation, Selection And Microgeographic Distribution, John. Elliott Jan 1982

Band Pattern In Helix Aspersa: Variation, Selection And Microgeographic Distribution, John. Elliott

Theses Digitization Project

No abstract provided.