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The Systematics And Biology Of The Genus Zapus (Mammalia, Rodentia, Zapodidae), Gwilym S. Jones Dec 1981

The Systematics And Biology Of The Genus Zapus (Mammalia, Rodentia, Zapodidae), Gwilym S. Jones

All-Inclusive List of Electronic Theses and Dissertations

This study was undertaken to determine specific and intraspecific relationships within the genus Zapus (Mammalia, Rodentia, Zapodidae). Subspecies are based on the biological subspecies concept where the subspecies is an evolutionary step between a population and species. Approximately 20,000 Recent specimens and representatives of fossil taxa were examined. Cranial and postcranial characteristics, colors, and when available bacula, sperms and karyotypes were incorporated into the morphological analyses. In addition, published biological data were summarized and analyzed for evidence of primary and secondary isolating mechanisms. Supplemental data were acquired during collection of 450 specimens in midwestern and western United States, western Canada, …


Optimum Yield And The Fcma: Uneven Distribution Of Management Burden, Herrick J. Johnson Dec 1981

Optimum Yield And The Fcma: Uneven Distribution Of Management Burden, Herrick J. Johnson

Marine Affairs Theses and Major Papers

Until the establishment of the Fishery Conservation and Management Act of 1976 (FCMA), fish outside the United States' twelve mile fishery zone were, according to international law, common property and belonged to the nation or individual that caught them. This common property law was based on the concept that fish resources were so large that no amount of fishing would interfere with the right of others to catch fish. Modern technology, however, has created equipment that enabled foreign and domestic fishermen to over-fish the resource. A reduced domestic catch led coastal fishermen to support a bill that unilaterally extended the …


A Forecasting-Programming Method For Swine Production-Marketing Decisions, Larry Janssen, James B. Hassler Oct 1981

A Forecasting-Programming Method For Swine Production-Marketing Decisions, Larry Janssen, James B. Hassler

Nebraska Agricultural Experiment Station: Historical Research Bulletins

This study reports on the development and progress of a forecasting-programming model for swine inventory management and marketing decisions. This model considers interrelationships between breeding herd, feeder pig and finishing hog activities. Objectives were: 1. To structure a dynamic operational decision model for a modern farrow-to-finish swine confinement unit which conforms with economic theory, uses price and cost forecast information and is as consistent as possible with current production scheduling practices. 2. To use and test this model during a combined production and marketing decision process and to compare economic results with results of a standard strategy.


Feasibility Study For A Beaver Reservoir Agricultural Water Supply Volume I, James Ferguson, Robert Shulstad, William Bateman Oct 1981

Feasibility Study For A Beaver Reservoir Agricultural Water Supply Volume I, James Ferguson, Robert Shulstad, William Bateman

Arkansas Water Resources Center Technical Reports

An irrigation district of approximately 30,000 acres has been proposed to be located in Washington and Benton Counties in Northwest Arkansas utilizing water from Beaver Reservior. This report on the economic benefits of such a district is done under contract No. DACW03-81-C for the U.S. Army Corps of Engineers by the Water Resources Research Center at the University of Arkansas.


Feasibility Study For A Beaver Reservoir Agricultural Water Supply Volume Ii, James Ferguson, Robert Shulstad, William Bateman Oct 1981

Feasibility Study For A Beaver Reservoir Agricultural Water Supply Volume Ii, James Ferguson, Robert Shulstad, William Bateman

Arkansas Water Resources Center Technical Reports

An irrigation district of approximately 30,000 acres has been proposed to be located in Washington and Benton Counties in Northwest Arkansas utilizing water from Beaver Reservior. This report on the economic benefits of such a district is done under contr


The Ecology Of Maine's Intertidal Habitats : A Report Prepared For The Maine State Planning Office, Peter F. Larsen, Lee F. Doggett Oct 1981

The Ecology Of Maine's Intertidal Habitats : A Report Prepared For The Maine State Planning Office, Peter F. Larsen, Lee F. Doggett

Maine Collection

The Ecology of Maine's Intertidal Habitats : A Report Prepared for the Maine State Planning Office

by Bigelow Laboratory for Ocean Sciences (Authors: Peter F. Larsen and Lee F. Doggett) , 1981.

Contents: Acknowledgements / List of Tables / List of Figures / Chapter 1 - Introduction / Chapter 2 - Human Impact on Intertidal Fauna / Chapter 3 - A Primer of Intertidal Ecology / Chapter 4 - A Sampler of Intertidal Species / Chapter 5 - Methodology / Chapter 6 - Results of Faunal Studies / Appendix 1 - Habitats With Date Sampled / Appendix 2 - List …


The Microbial Biochemical Potential Of Two Detention-Retention Marshes In The Kissimmee River Valley Watershed, Douglas A. Winkelmann Oct 1981

The Microbial Biochemical Potential Of Two Detention-Retention Marshes In The Kissimmee River Valley Watershed, Douglas A. Winkelmann

Retrospective Theses and Dissertations

One of the major programs to abate the deterioration of water quality in the Lake Okeechobee watershed was the addition of detention-retention facilities. The microbial biochemical potential of two different detention-retention marshes in the Kissimmee River Valley were examined to determine their effectiveness to improve water quality. The kinetics of decomposition and nutrient mineralization and assimilation, as mediated by microorganisms, and the enumeration of microorganisms capable of utilizing various substrates were studied. Various communities within each marsh were studied during a 2-year period. The decomposition rates of 3 plant substrates were determined. Chitin was used as a standard for organic …


A Quantitative Description Of Migratory Behavior Of The Brown Shrimp (Penaeus Aztecus) With Applications In Fisheries Management, Anne Madolyn Babcock Oct 1981

A Quantitative Description Of Migratory Behavior Of The Brown Shrimp (Penaeus Aztecus) With Applications In Fisheries Management, Anne Madolyn Babcock

OES Theses and Dissertations

A quantitative description of the migratory behavior of the brown shrimp, Penaeus aztecus, was established using the density approach. A theoretical time density was estimated by the proportion of catch and catch per boat hour NOAA-NMFS fisheries statistics collected in Pamlico Sound, the Neuse River, and Core Sound. A clear quantitative description of brown shrimp migratory timing is found in the time densities. The impact of various physical tactors on the progress of the fishery in time and space can be objectively evaluated by using the time density statistics as dependent variables in modeling efforts. The distributions also enable …


The Prairie Naturalist Volume 13, Numbers 3 And 4. September - December 1981 Oct 1981

The Prairie Naturalist Volume 13, Numbers 3 And 4. September - December 1981

The Prairie Naturalist

PROVISIONAL CHECKLIST OF MAMMALS OF SOUTH DAKOTA ▪ J. R. Choate and J. K. Jones, Jr.

LABORATORY FEEDING PREFERENCES OF THREE SMALL MAMMALS FOR FIVE TREE SPECIES ▪ T. G. Barnes and T. A. Schaid

NESTLING DIETS OF RED-WINGED AND YELLOW-HEADED BLACKBIRDS ON PLAYA LAKES OF WEST TEXAS ▪ D. H. Fischer and E. C. Bolen

COMPARISON OF FOUR NORTH DAKOTA IMPOUNDMENTS AND FACTORS AFFECTING

THE DEVELOPMENT OF IMPOUNDMENT PARASITOFAUNA ▪ H. L. Holloway, Jr. and N. T. Hagstrom

FIRST STATE RECORD OF RICHARDSON'S GROUND SQUIRREL IN IOWA ▪ R. P. Lampe, J. B. Bowles, and R. Spengler

THE EFFECT …


Algal Dynamics In A Cypress Stand In The Seasonally Flooded Great Dismal Swamp, Joseph A. Atchue Iii Oct 1981

Algal Dynamics In A Cypress Stand In The Seasonally Flooded Great Dismal Swamp, Joseph A. Atchue Iii

Biological Sciences Theses & Dissertations

The dynamics of epiphytic algae and phytoplankton were studied at a cypress stand in the Great Dismal Swamp, Virginia. Mean epiphytic algal biomass was 19.9 g m-2 and mean planktonic biomass was 3.4 g m-2.Nutrient concentrations in the epiphytic algae and the litter were determined. The algae had mean concentrations of 1.67% and 0.18%. They were found to immobilize as much as 0.5 g N m-2 and 0.06 g P m-2. This suggests that the algae are important as nutrient conservers. The phytoplankton were composed primarily of Bacillariophyceae. They exhibited a more or less …


State Of The Fisheries Report 1980, Department Of Fisheries And Wildlife, Western Australia Sep 1981

State Of The Fisheries Report 1980, Department Of Fisheries And Wildlife, Western Australia

Status Reports of the Fisheries and Aquatic Resources

Western Australia has maintained its position as the top fishing State. The catch in Western Australia of fish, crustaceans and molluscs in 1979/80 was worth $85.7 million to the fishermen, which is 27 per cent of the total value for Australia.


Santa Clara Magazine, Volume 24 Number 1, Fall 1981, Santa Clara University Sep 1981

Santa Clara Magazine, Volume 24 Number 1, Fall 1981, Santa Clara University

Santa Clara Magazine

3- MEDIA AND MASS PSYCHOLOGY A not too gentle probe of the news media today. By Jerome Kroth.

9 - SAINTS, DIAMONDS AND BEARS A thoughtful comparison of education , today and 40 years ago. By William J. Rewak, S.J.

12 - SANTA CLARA POTPOURRI A chance to test your memory of campus features.

14 - THREE FOR ALL SEASONS Examining the interrelationship of three great Christian humanists. By Christiaan T. Lievestro.

18 - WHERE IS LOVE? Defining love in the new Catholic marriage law. By Theodore Mackin, S.J.

23 - TRACKING THE HIGH TECH BOOM The Silicon Valley is …


Back Matter Sep 1981

Back Matter

Henry Ford Hospital Medical Journal

No abstract provided.


Proceedings Of 14th Conference Prairie Grouse Technical Council. September 23-25, 1981: Halsey, Nebraska Sep 1981

Proceedings Of 14th Conference Prairie Grouse Technical Council. September 23-25, 1981: Halsey, Nebraska

Nebraska Game and Parks Commission: White Papers, Conference Presentations, and Manuscripts

HOST: Nebraska Game and Parks Commission

INTRODUCTION - Jim Mitchell, Upland Game Specialist, Nebraska Game and Parks Commission (Conference Coordinator)

WELCOME - Bill Bailey, Assistant Director, Nebraska Game and Parks Commission

IN MEMORIAM — This publication is dedicated to Ken Robertson

THE NEBRASKA SANDHILLS - AN OVERVIEW, Jon Farrar, Nebraska Game and Parks Commission

PRAIRIE GROUSE IN THE SANDHILLS, Carl W. Wolfe, Nebraska Game and Parks Commission

GROUSE ON fflE BESSEY DIVISION NEBRASKA NATIONAL FOREST, Steve Marquardt, U.S. Forest Service

EXPERIMENTAL SHARP-TAILED GROUSE INTRODUCTIONS IN PENNSYLVANIA, John J. Kriz, Pennsylvania Game Commission

ANALYSIS OF GREATER PRAIRIE CHICKEN POPULATION AND HARVEST …


Connquest, Sandra Cookson, D.W. Allinson, G.S. Speer, R.W. Taylor, R.P. Prince, J.W. Bartok, D.W. Protheroe, D.R. Miller Aug 1981

Connquest, Sandra Cookson, D.W. Allinson, G.S. Speer, R.W. Taylor, R.P. Prince, J.W. Bartok, D.W. Protheroe, D.R. Miller

Storrs Agricultural Experiment Station

No abstract provided.


Kentucky Warbler (Vol. 57, No. 3), Kentucky Library Research Collections Aug 1981

Kentucky Warbler (Vol. 57, No. 3), Kentucky Library Research Collections

The Kentucky Warbler

No abstract provided.


The Effect Of Hypercholesterolemia On The Membrane Lipids, 3-0-[¹⁴C] Methylglucose Transport, And 2,3-Diphosphoglycerate Levels In Rat Erythrocytes, Edwin J. Lester Jr. Aug 1981

The Effect Of Hypercholesterolemia On The Membrane Lipids, 3-0-[¹⁴C] Methylglucose Transport, And 2,3-Diphosphoglycerate Levels In Rat Erythrocytes, Edwin J. Lester Jr.

Loma Linda University Electronic Theses, Dissertations & Projects

An increase in dietary cholesterol and cholic acid will produce hypercholesterolemia in rats. For ten months, two groups of rats (six in each group) were fed commercial rat pellets (control group) or rat pellets plus cholesterol (1%) and cholic acid (0.25%) (experimental group). A blood sample from each animal was divided into three aliquots for three separate experiments on the erythrocytes: a membrane cholesterol and phospholipid determination, a 3-0-[14C] methylglucose (30MG) transport determination, and a 2,3-diphosphoglycerate (2,3 DPG) determination. The 30MG transport and 2,3 DPG aliquots were each incubated in the same five concentrations of 30MG and glucose …


The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of Pinealectomized Male Mice Mus Musculus, Icr Strain, John Earnest Constantine Aug 1981

The Effects Of Photoperiod And Melatonin Injections On The Reproductive System Of Pinealectomized Male Mice Mus Musculus, Icr Strain, John Earnest Constantine

Master's Theses

One hundred two male mice , Mus musculus, ICR strain, age four weeks, were obtained. Fifty-one mice were pinealectomized and 51 were sham operated. The animals were divided into three photoperiod groups: 1.5L:22.5D, 14L:10D, 24L; 0D. The mice were subcutaneously injected daily with 10 ug melatonin or control solution from post-operative day J to post-operative day 60, On post-operative day 60 representatives of each photo­ period-surgery-injection regimen were paired with females. The remaining animals were killed and several organs were removed and weighed, Melatonin injections were progonadal in pinealectomized mice and inhibitory in sham mice in several instances. Histological examination …


Preliminary Nutrient Uptake Studies Of Experimental Vegetative Covers At The Maxey Flat Low-Level Nuclear Waste Disposal Site, Donna Lynn Cassity Jul 1981

Preliminary Nutrient Uptake Studies Of Experimental Vegetative Covers At The Maxey Flat Low-Level Nuclear Waste Disposal Site, Donna Lynn Cassity

Morehead State Theses and Dissertations

A thesis presented to the faculty of the School of Sciences and Mathematics at Morehead State University in partial fulfillment of the requirements for the Degree of Master of Science in Biology by Donna Lynn Cassity on July 27, 1981.


Notes On Recent Changes In Tanaidacean Terminology, Charles G. Messing Jul 1981

Notes On Recent Changes In Tanaidacean Terminology, Charles G. Messing

Marine & Environmental Sciences Faculty Articles

no abstract available


Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan Jul 1981

Diagenesis Of Organic Matter In Las Vegas Bay And Bonelli Bay, Lake Mead, James W. Murray, Carolyn J. Jones, Kathy Kuivila, Jeff Sawlan

Publications (WR)

The interstitial water chemistry of the sediments of Las Vegas Bay and Bonelli Bay in Lake Mead has been studied as part of a comprehensive water quality study of those locations. Pore water and solid phase analyses were completed from four stations in Las Vegas Bay and two stations in Bonelli Bay. At both locations the pore water compositions and organic matter diagenesis in the sediments are dominated by sulfate reduction. This major role of sulfate reduction is unusual for lake sediments and reflects the fact that SO4 is the major anion in the lake water. In addition, gypsum …


Petroleum-Utilizing Bacteria: The Biological Line Defense Against Oil Pollution, Steven W. Sokolowski Jul 1981

Petroleum-Utilizing Bacteria: The Biological Line Defense Against Oil Pollution, Steven W. Sokolowski

Biological Sciences Theses & Dissertations

A silica gel-petroleum (SGP) medium was developed which is reliable, approximately the same cost as that of the corresponding agar-based petroleum medium, and can be made sufficiently firm to use in streaking or the spread-plate technique. Advantages of the medium include: the incorporation of all of the major ions of seawater in accordance with Dittmar's Law (the salinity of which can easily be varied from 0 to 35 parts per thousand); a wide workable pH range (5.5 to 11.6); negligable pH drift(~ 0.2 pH units after 166 days); the elimination of all but negligable amounts of syneresis, the ability to …


Back Matter Jun 1981

Back Matter

Henry Ford Hospital Medical Journal

No abstract provided.


Mechanisms Of Control Of Blood Flow In The Forelimb Of Sheep, Paul J. Marks Jun 1981

Mechanisms Of Control Of Blood Flow In The Forelimb Of Sheep, Paul J. Marks

Loma Linda University Electronic Theses, Dissertations & Projects

Although much is known about the factors involved in the control of blood flow, the cellular mechanisms of their action are poorly understood. This study investigated the mechanisms of norepinephrine, epinephrine, isoproterenol, and acetylcholine.

First, in a constant pressure/variable flow preparation we characterized the sheep brachial artery blood flow response to, and recovery from, 10-min infusions of each of these drugs. Then we used a computer model to simulate changes in blood flow in response to altered ion permeabilities or pump speeds (the mechanisms). We tried to produce responses like those to the drug infusions so that we could infer …


Chemical And Biological Structure Of Lake Mead Sediments, Richard T. Prentki, Larry J. Paulson, John R. Baker Jun 1981

Chemical And Biological Structure Of Lake Mead Sediments, Richard T. Prentki, Larry J. Paulson, John R. Baker

Publications (WR)

Lake Mead has undergone a serious decline since Glen Canyon Dam was constructed 450 km upstream in 1963.

State fisheries management agencies are concerned that the decline was caused by water level fluctuations and more severe drawdowns during the bass spawning season, when the operation of Hoover Dam was altered during the post-Lake Powell period.

The construction of Glen Canyon Dam and formation of Lake Powell in 1963 drastically altered the natural discharge and temperature cycles and decreased suspended sediment and nutrient loading in the Colorado River inflow to Lake Mead. Recent studies indicate that these changes in nutrient loading …


The Prairie Naturalist Volume 13, Number 2. June 1981 Jun 1981

The Prairie Naturalist Volume 13, Number 2. June 1981

The Prairie Naturalist

HERPETOFAUNA OF MORMON ISLAND PRESERVE, HALL COUNTY, NEBRASKA ▪ S. M. Jones, R. E. Ballinger and J. W Nietfeldt

COYOTE USE OF PLAYAS IN THE TEXAS HIGH PLAINS ▪ R. W. Whiteside and F. S. Guthery

NEW RECORD OF THE LEAST WEASEL IN WYOMING ▪ M. R. Stromberg, D. E. Biggens and M. Bidwell

STATUS OF AMERICAN WOODCOCK IN NEBRASKA WITH NOTES ON A RECENT BREEDING RECORD ▪ G. R. Lingle

WINTER FOODS OF THE PINE GROSBEAK IN EASTERN NORTH DAKOTA ▪ R. C. Reigh

SEASONAL VARIATION IN HOME RANGE OF A FEMALE BADGER (Taxidea taxus) ▪ R. …


A Morphometrical Analysis Of The Guinea Pig Placenta After Chronic Exposure To Carbon Monoxide, Marcella J. Woolsey Jun 1981

A Morphometrical Analysis Of The Guinea Pig Placenta After Chronic Exposure To Carbon Monoxide, Marcella J. Woolsey

Loma Linda University Electronic Theses, Dissertations & Projects

We used morphometric analysis to determine if placental structure is modified by carbon monoxide, Camm-Hartley guinea pigs were exposed throughout gestation to chronic conditions of carbon monoxide (averaging about 180 parts per million). Maternal weight, placental weight, fetal weight, and fetal length were recorded at the time of placental fixation. Using a computerized image analyzer on photomicrographs obtained through light microscopy, we measured maternal and fetal percent vessel volumes, surface areas, and vessel numbers. Maternal vessel numbers and surface area remained basically unchanged but decreased slightly. Maternal percent volume decreased 15%. However, fetal capillary number increased 35% (p < 0.01) from a control value of 2325 ± 184 per mm2 (SE …


Diversity And Production Of Herbaceous Vegetation In A Northern Utah Subalpine Chronosequence, Gary A. Reese May 1981

Diversity And Production Of Herbaceous Vegetation In A Northern Utah Subalpine Chronosequence, Gary A. Reese

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Successional trends in herbaceous plant production and diversity were studied in an age sequence of sites, i.e. chronosequence, inferred to represent a meadow to aspen to fir to spruce-fir sere. Primary production was observed to decrease in a linear fashion with successional development. Three components of diversity; richness, heterogeneity, and equitability or evenness, each had low early successional values, reaching maximum diversity in mid-succession, and declining to intermediate levels with maturity. The magnitude of these trends varied greatly, depending on the methods used to determine plant dominance. Characteristics of various dominance indices and their applicability to this study were examined. …


Fall Regrowth Of Crested Wheatgrass And Fourwing Saltbush, Noor Mohammad May 1981

Fall Regrowth Of Crested Wheatgrass And Fourwing Saltbush, Noor Mohammad

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

During 1980-81, studies with crested wheatgrass (Agropyron desertorum) and fourwing saltbush (Atriplex canescens) were conducted in controlled environment growth chambers as well as under field conditions to achieve the following objectives:

1. To determine the effect of nitrogen fertilizer on the water use efficiency.

2. To determine the effects of various temperature, water stress and nitrogen treatments on the productivity, nitrogen content and carbohydrate reserves.

3. To determine the effects of N fertilization on fall and spring regrowth.

Crested wheatgrass and fourwing saltbush plants were maintained in three growth chambers for 60 days under three temperature …


The Economic Impact Of Potential Changes In Federal Grazing Policies On Ranchers In Wayne County, Utah, Kib Elden Jacobson May 1981

The Economic Impact Of Potential Changes In Federal Grazing Policies On Ranchers In Wayne County, Utah, Kib Elden Jacobson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this study was to select an area in Utah that was predominantly livestock oriented which used federal lands for livestock grazing, and to develop model ranches exemplifying the typical live-stock operation in the area. These model ranches were then used in a Budget Generator Program (BG) and a Linear Programming framework (LP) to simulate reductions of 25%, 50%, 75% and 100% reductions of BLM land usage. The results were then used to determine income changes, herd size changes, and resource usage in the models as the reductions took place.

The area chosen was Wayne County, Utah because …