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Shell-Dropping Behavior Of Western Gulls (Larus Occidentalis), John L. Maron Jul 1982

Shell-Dropping Behavior Of Western Gulls (Larus Occidentalis), John L. Maron

Biological Sciences Faculty Publications

Westem Gulls (Larus occidentalis) at Bodega Bay, California drop shelled prey items to break them. I presented Washington clams (Saxidomus nuttalli) of known weight to free-flying gulls to investigate factors affecting shell-dropping behavior. All adult gulls dropped clams, whereas only 55% of immature gulls did so. The other 45% of immature gulls that were given clams pecked at them on the ground instead. Gulls dropped clams on both hard and soft substrates. Flight distance and kleptoparasitism seemed important in influencing drop location. Adult Western Gulls dropped heavy clams from lower heights than they dropped light clams. …


Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln Jul 1982

Farm, Ranch And Home Quarterly Institute Of Agriculture And Natural Resources, University Of Nebraska- Lincoln

Farm, Ranch and Home Quarterly

In this issue:

An Investment Returned ....................... 2

The Northeast Station- 25 years of Research, Extension and Service......... 3

Opportunities and Obstacles- Women Choose Agricultural Careers.............. 11

The Animal Welfare Movement- Where did it come from and where is it going?.............. 14

Center Pivot Irrigation- Runoff Analyzed on Sloping, Clayey Soil .................. 16

Nitrogen Management- Soils Change in Nutrient Content......................... 18

New Directions in Research ................................ 20


Some Variations In Distribution Of Fishes In Large Mainstream Reservoirs Associated With Artificial Cover, Donald W. Johnson, Elizabeth M. Choinski Jul 1982

Some Variations In Distribution Of Fishes In Large Mainstream Reservoirs Associated With Artificial Cover, Donald W. Johnson, Elizabeth M. Choinski

KWRRI Research Reports

The influence of artificial cover (brush piles) on fish populations in Kentucky Lake and Lake Barkley was studied. Mature and larval fishes were collected from deep and shallow sites with and without cover in a bay of each lake. Highest densities of mature crappie, bass, and sauger were found adjacent to deep attractors, while larval crappie and minnows were most concentrated at shallow brush piles. Shad (both adult and larvae) were not congregated at attractor sites. Information gathered supports the continuation of artificial cover installation and water level management procedures which will provide high and stable levels through spring spawning …


An Ecological Analysis Of Relic Diatoms In Sediments Of Las Vegas Bay, Lake Mead, David Ross Hetzel Jul 1982

An Ecological Analysis Of Relic Diatoms In Sediments Of Las Vegas Bay, Lake Mead, David Ross Hetzel

Publications (WR)

Relic diatoms in sediments of the inner Las Vegas Bay, near the Las Vegas Wash sewage inflow, were examined in order to assess historic trophic conditions in this area of Lake Mead. Diatom sedimentation rates and ratios of Araphidineae/Centrales (A/C) diatom groups were determined from sediment cores collected in the old wash channel 1.5 km from the sewage inflow (station 2), in a small cove 1.5 km further downstream (station 3) and in an adjacent embayment off Gypsum Wash (station 4). Diatom sedimentation rates generally increased from the bottom to the top of each core, but pronounced minima existed at …


Review: Land Use In America, Perry J. Brown Jul 1982

Review: Land Use In America, Perry J. Brown

Forest Management Faculty Publications

No abstract provided.


The Influence Of Somatic Investment On The Patterns Of Reproduction In Poecilia Latipinna (Pisces: Poeciliidae), Jeffrey D. Wetherington Jul 1982

The Influence Of Somatic Investment On The Patterns Of Reproduction In Poecilia Latipinna (Pisces: Poeciliidae), Jeffrey D. Wetherington

Retrospective Theses and Dissertations

In Poecilia latipinna size-specific reproductive and survivorship patterns were correlated with changes in habitat availability. Of the numerous physical, chemical, and biological parameters associated with a reduction in available habitat, probably the most important was reduced food availability. Large (old) females, theoretically with a low reproductive value, allocated energy to reproduction regardless of habitat and, presumably, food availability. When reproductive activities were initiated in March, habitat availability was modest. In association with a severe reduction in available habitat in April, large females were subject to a substantial loss of body weight during the yolk-loading phase of the reproductive cycle. This …


Electroimmunoassay: A New Competitive Protein Binding Assay Using Antibody Selective Electrodes, George Raymond Connell Jul 1982

Electroimmunoassay: A New Competitive Protein Binding Assay Using Antibody Selective Electrodes, George Raymond Connell

Chemistry & Biochemistry Theses & Dissertations

The purpose of this study was to utilize the concept of antibody selective electrodes to developed a new competitive protein binding assay. This is a new concept and a potentially important analytical technique because it combines the advantages of RIA (sensitivity and selectivity) with the advantages of electrical assays (speed and low cost). A conjugate of PGE2 and dibenzo—18- crown-6 (a cation selective ionophore) was synthesized, and incorporated into a plastic membrane. The ionophore conjugate increased the selectivity of a polyvinyl chloride (PVC) membrane to monovalent cations. Transmembrane potential was altered by anti-PGE2 antisera in a concentration dependent …


Isomers Of 5.8s Ribosomal Rna, David Smith Jul 1982

Isomers Of 5.8s Ribosomal Rna, David Smith

Chemistry & Biochemistry Theses & Dissertations

When whole cell RNA was separated by high resolution PAG (i.e., polyacrylamide gel) electrophoresis, 5.8S rRNA migrated as three higher mobility intense bands, and three faint bands of lower mobility. The three intense bands represent conformational isomers which migrated as a single band under denaturing conditions on PAG. The three faint bands represent conformational isomers of a minor form of 5.8S rRNA which is elongated at the 5' terminus of the molecule. This minor form migrates as a single band of lower mobility than the major form when electrophoresed on a denaturing PAG. The minor form was determined to have …


Feeding Behavior Of Three Species Of Spionid Polychaetes, Thomas Lane Stokes Jr. Jul 1982

Feeding Behavior Of Three Species Of Spionid Polychaetes, Thomas Lane Stokes Jr.

Biological Sciences Theses & Dissertations

Observations of feeding behavior of three species of spionid polychaetes (Paraprionospio pinnata, Polydora ligni, and Streblospio benedicti) were performed in currents ranging from 0 to 10 cm/sec over fine and coarse sediments and in high and low suspended particle loads. These interface feeders may suspension feed, deposit feed, or both simultaneously using a pair of anterior tentaculate feeding palps. P. ligni and S. benedicti were found to alter their palp behaviors in response to experimental manipulations. P. ligni reacted strongly to currents by suspension feeding with coiled palps. S. benedicti reacted strongly and complexly to food particle type and availability. …


Variation In Leaf Macronutrients Of Overstory Trees As Influenced By Species Season And Soil Type In The Great Dismal Swamp Of Virginia, Bruce J. Bandle Jul 1982

Variation In Leaf Macronutrients Of Overstory Trees As Influenced By Species Season And Soil Type In The Great Dismal Swamp Of Virginia, Bruce J. Bandle

Biological Sciences Theses & Dissertations

Leaf macronutrient variation was studied in four plant communities in the Dismal Swamp of Virginia. composition differed markedly between these sites. Soils and species Eight important overstory trees were studied in August 1980; whereas red maple (Acer rubrum L.} and black gum (Nyssa sylvatica Marsh.}, which occurred on all four sites, were sampled seasonally. Significant differences (p .05) were found in the nutrient concentrations of the leaves between species, seasons, and sites. These differences may be attributed to inherent species characteristics, leaf expansion, nutrient translocation, and differences in soil organic matter content, pH, and degree of …


Electroimmunoassay A New Competitive Protein Binding Assay Using Antibody Selective Electrodes, George Raymond Connell Jul 1982

Electroimmunoassay A New Competitive Protein Binding Assay Using Antibody Selective Electrodes, George Raymond Connell

Chemistry & Biochemistry Theses & Dissertations

The purpose of this study was to utilize concept of antibody selective electrodes to develop a new competitive protein binding assay. This is a new concept and potentially important analytical technique because it combines the advantage of RIA (sensitivity and selectivity) with advantages of electrical assays (speed and low cost).


Development Of A Procedure For Analysis Of High Density Lipoprotein Subclasses, Chan Chin Jul 1982

Development Of A Procedure For Analysis Of High Density Lipoprotein Subclasses, Chan Chin

Chemistry & Biochemistry Theses & Dissertations

Human serum high density lipoprotein subclasses, HDL2 and HDL3 , were isolated by preparative salt density gradient ultracentrifugation and further analyzed by electrophoresis on a 4 to 15% concentration gradient polyacrylamide gel.

The separation of the major classes of serum lipoproteins was achieved after a single ultracentrifugation for 272,000 g at 15°c in a swinging bucket rotor. High resolution concentration gradient gel electrophoresis was found to be particularly suitable for the separation of lipoproteins. The isolation of HDL by precipitation methods, heparin-manganese and dextran-magnesium have also been evaluated in this study, and were found not to completely separate …


Determining The Uptake And Possible Assimilation Of The Plant Component Of Spartina Detritus By Palaemonetes Pugio Using A Rapid Radiolabeling Method, Michael Peter Crosby Jul 1982

Determining The Uptake And Possible Assimilation Of The Plant Component Of Spartina Detritus By Palaemonetes Pugio Using A Rapid Radiolabeling Method, Michael Peter Crosby

Biological Sciences Theses & Dissertations

Assimilation of the plant components of Spartina alterniflora detritus by the grass shrimp, Palaemonetes pugio, was investigated in a laboratory feeding study. A new radiolabeling procedure was utilized to label the sterilized detritus with 14C. Organic carbon values were calculated for both S. alterniflora and P. pugio. The grass shrimp were found to assimilate significantly the detritus, with an assimilation efficiency of approximately 14%, and an approximate ingestion rate of 2.508 x l0-4mg C detritus/mg C shrimp hour-l occurred. It is hypothesized that coprophagous activity may be important to the completion of digestion of …


The Effects Of Kepone On The Estuarine Copepod Acartia Tonsa, Judith Marie Wilson Jul 1982

The Effects Of Kepone On The Estuarine Copepod Acartia Tonsa, Judith Marie Wilson

Biological Sciences Theses & Dissertations

Due to the contamination of a 113 km reach of the James River, Kepone poses a serious environmental threat to the Chesapeake Bay. The purpose of the study is to determine the acutely toxic and sublethal levels of kepone for the copepod Acartia tonsa, and to investigate what effects those levels may have on filtration rates.

Kepone was determined to be acutely toxic to A. tonsa, with a 96 hour LC50 of 4.96 ug/1. Dunaliella tertiolecta was selected as the food source for the grazing experiments. Kepone concentrations of 0.046 ug/1 significantly (0.05 level) reduced the flltering rate …


Development Of An On-Line Computer System For Enzyme Kinetics Studies, Jacqueline R. Thweatt Jul 1982

Development Of An On-Line Computer System For Enzyme Kinetics Studies, Jacqueline R. Thweatt

Chemistry & Biochemistry Theses & Dissertations

The PDP-11/10 minicomputer was interfaced to the Beckman 25 ultraviolet/visible spectrophotometer and this on-line computer system was applied to enzyme kinetics studies. This interface involved hardware equipment to locate, amplify, and transmit the analog signal to an analog-to-digital converter, and software to acquire and store the digital data. Data processing programs were used to calculate kinetic parameters and statistical information from the acquired data.

The Varian Cary 219 ultraviolet/visible spectrophotometer can be readily interfaced to the Apple II Plus microcomputer by hardware equipment which can be purchased from the manufacturer. Various software may also be purchased for use in enzyme …


An Ecological Study Of The Troglobitic Cirolanid Isopod Antrolana Lira Bowman From Madisons Saltpetre Cave And Stegers Fissure, Augusta Co., Virginia, T. Lynn Collins Jul 1982

An Ecological Study Of The Troglobitic Cirolanid Isopod Antrolana Lira Bowman From Madisons Saltpetre Cave And Stegers Fissure, Augusta Co., Virginia, T. Lynn Collins

Biological Sciences Theses & Dissertations

An ecological study of the troglobitic cirolanid isopod, Antrolana lira Bowman, was begun in August 1979 and continued through September 1980. The isopod is restricted to two phreatic lakes in Madisons Saltpetre Cave and one phreatic lake in nearby Stegers Fissure, Augusta Co., Virginia.

All three phreatic lakes were scuba dived and surveyed. No direct connections were found between the lakes. However, physical similarities suggest that the lakes are made up of the same body of phreatic water.

Random samples were taken monthly and seasonally from the east lake in Madisons Saltpetre Cave and the lake in Stegers Fissure. Specimens …


Interbasin Transfer Economics: The High Plains Region, Allen Kneese Jun 1982

Interbasin Transfer Economics: The High Plains Region, Allen Kneese

New Sources of Water for Energy Development and Growth: Interbasin Transfers: A Short Course (Summer Conference, June 7-10)

44 pages (includes 1 map).


Parallel-Arm Maze Performance Of Sighted And Blind Rats: Spatial Memory And Maze Structure, Robert H.I. Dale Jun 1982

Parallel-Arm Maze Performance Of Sighted And Blind Rats: Spatial Memory And Maze Structure, Robert H.I. Dale

Scholarship and Professional Work - LAS

Sighted and peripherally blinded groups of rats learned to obtain a small reward from each arm of an eight-arm parallel maze, and a sighted group was similarly trained on a radial maze. The parallel-sighted and parallel-blind groups were equally slow, and much slower than the radial-sighted group, to attain criterion performance. The three groups shared several response characteristics: selectively avoiding the most recently entered arms, frequently choosing adjacent arms, and an absence of 'spatial generalization' among the arms. The findings support a simple model proposing how subjects identify and choose among the maze-arms.


U.S. Declares War On Coyotes Jun 1982

U.S. Declares War On Coyotes

Close Up Reports

The coyote has long been perceived as a threat by ranchers who graze their sheep on U.S. public lands. At the ranchers' insistence, U.S. government employees are paid to shoot coyotes from helicopters and airplanes, ambush them in cruel steel-jaw leghold traps, and plant cyanide guns that explode in the coyotes' faces. The Humane Society of the United States is irrevocably opposed to the unabated, cruel, and unnecessary practice of killing animals in the name of "predator control." The resumed use of denning and the threat of reinstituting 1080 makes our--and your--actions even more urgent.


Agricultural Experiment Station News June 1982 Jun 1982

Agricultural Experiment Station News June 1982

Agricultural Research Division: News and Annual Reports

CONTENTS:
From the Director’s Desk
Widaman Trust Awards to Twelve
SAHS SEZ
New AES Project Outline Format
NEW AND REVISED PROJECTS
Grants and Contracts
New Experiment Station Personnel
Journal Articles - Submitted for Publication
Journal Abstracts - Submitted for Publication
BULLETINS PRINTED
CALENDAR OF EVENTS - SUMMER, 1982


The Cytoskeletal System Of Nucleated Erythrocytes. I. Composition And Function Of Major Elements, William D. Cohen, Diana Bartelt, Richard Jaeger, George M. Langford, Iris Nemhauser Jun 1982

The Cytoskeletal System Of Nucleated Erythrocytes. I. Composition And Function Of Major Elements, William D. Cohen, Diana Bartelt, Richard Jaeger, George M. Langford, Iris Nemhauser

Biology - All Scholarship

We have studied the dogfish erythrocyte cytoskeletal system, which consists of a marginal band of microtubules (MB) and trans-marginal band material (TBM). The TBM appeared in whole mounts as a rough irregular network and in thin sections as a surface-delimiting layer completely enclosing nucleus and MB. In cells incubated at 0 degrees C for 30 min or more, the MB disappeared but the TBM remained. MB reassembly occurred with rewarming, and was inhibited by colchicine. Flattened elliptical erythrocyte morphology was retained even when MBs were absent. Total solubilization of MB and TBM at low pH, or dissolution of whole anucleate …


Possible Evidence Of Fish-Eating By A Lesser Sandhill Crane From The Central Platte Valley, Nebraska, Myra Mergler Niemeier, Paul E. Niemeier Jun 1982

Possible Evidence Of Fish-Eating By A Lesser Sandhill Crane From The Central Platte Valley, Nebraska, Myra Mergler Niemeier, Paul E. Niemeier

Nebraska Bird Review

Centrarchid fish scales, probably those of the Green Sunfish (Lepomis cyanellus), were found in the crop of a Lesser Sandhill Crane (Grus canadensis canadensis) from the Central Platte Valley, Nebraska, in March, 1976. Scales were primarily from age class II fish. Fish total length was estimated at 100.60 mm.


Effect Of Levamisole On The Incidence Of Spontaneous Mammary Tumors In C3h Mice, Robert H. Page, Duilio A. Valdivia, Robert W. Talley, Robert A. Huseby Jun 1982

Effect Of Levamisole On The Incidence Of Spontaneous Mammary Tumors In C3h Mice, Robert H. Page, Duilio A. Valdivia, Robert W. Talley, Robert A. Huseby

Henry Ford Hospital Medical Journal

Spontaneous mammary carcinoma in C3H mice is preceded by premalignant hyperplastic alveolar nodules. When a primary tumor is evident, examination of the other mammae will reveal a number of microscopic precancerous lesions in various stages of transformation to overt malignant tumors. In an effort to inhibit the development of additional malignant tumors after surgical removal of the first apparent tumor, we treated female C3H/HeJ mice with subcutaneous injections of levamisole (0.6 mg per kg of body weight) on a twice weekly regimen. All further tumors were surgically excised when they became palpable. The surgical excision of bulk tumor burden, immunorestoration …


Acid Phosphatase: Clinical Utility Of The First Tumor Marker, Christopher J. Dipaolo, Jan Rival Jun 1982

Acid Phosphatase: Clinical Utility Of The First Tumor Marker, Christopher J. Dipaolo, Jan Rival

Henry Ford Hospital Medical Journal

Acid phosphatase was the first tumor marker to be measured in blood. Although it is used as a marker of prostatic carcinoma, serum levels are also elevated in many diseases of prostate, bone, and hematologic tissue. While serum acid phosphatase concentration is elevated in patients with prostatic carcinoma or infarction, it may also be increased merely with benign hypertrophy and after prostate massage. Recent studies demonstrate that levels are not significantly increased after routine rectal examination. Although of limited use as a screening test, the assay may be useful in staging, prognostication during hormonal therapy, and in making clinical decisions. …


Distributions, Densities, And Relative Abundances Of Grasshoppers (Orthoptera: Acrididae) In A Nebraska Sandhills Prairie, Anthony Joern Jun 1982

Distributions, Densities, And Relative Abundances Of Grasshoppers (Orthoptera: Acrididae) In A Nebraska Sandhills Prairie, Anthony Joern

Entomology Papers from Other Sources

Grasshoppers (Orthoptera: Acrididae) represent a conspicuous and often important component of grassland systems (Odum et al. 1962, Smalley 1960, Sinclair 1975, Van Hook 1971, Wiegert 1965). Often, assemblages of grasshoppers are quite diverse and may, on occasion, consume a large fraction of the available vegetation (Hewitt 1977, Hewitt et al. 1976, Mitchell and pfadt 1974). As such, grasshoppers have the potential of being very important in the nutrient and energy flow in grassland ecosystems. However, to understand the impact of grasshoppers at the ecosystem level requires that the densities and fluctuations of populations as well as the species composition of …


Dietary Effects On Pulmonary Function At 3780 Meters Altitude, Vicki Estes-Bruff Jun 1982

Dietary Effects On Pulmonary Function At 3780 Meters Altitude, Vicki Estes-Bruff

Loma Linda University Electronic Theses, Dissertations & Projects

Diet is known to affect acclimatization to altitude through the effect of carbohydrate on the respiratory exchange ratio. During the first three days following ascent to high altitude, spirometric indices including the forced vital capacity (FVC) and forced expiratory volume in one second (FEVp) decrease. The purpose of this study was to determine if dietary carbohydrate would influence these spirometric changes.

Seven healthy subjects were studied on two nutritionally complete diets at 335 meters and 3780 meters altitude in a cross-over design. The high carbohydrate diet (HI CHO) consisted of 76% of calories as carbohydrate, 12% as fat and 12% …


Observation Of Bone Formation In The Mandibular Symphysis Following Surgical Separation And Slow Mechanical Expansion In A Baboon, Robert J. Homer Jun 1982

Observation Of Bone Formation In The Mandibular Symphysis Following Surgical Separation And Slow Mechanical Expansion In A Baboon, Robert J. Homer

Loma Linda University Electronic Theses, Dissertations & Projects

Mechanical expansion of the maxilla, at the midline suture, is a widely accepted orthodontic procedure used to gain arch width in certain types of maxillary deficient arches.

In animal research on the mandible, techniques using surgical separation at the symphysis with immediate expansion up to 12 mm, fixation with a metal splint, and autogenous bone transplanted into the expanded area, have been reported to be successful.

To date, no experiment utilizing slow mechanical expansion of the mandible at the symphysis has been reported.

In this pilot study, the mandible of a female baboon was surgically separated A-P at the symphysis. …


Mast Cell Histamine Release Induced By Portuguese Man-Of-War (Physalia) Venom, A. Lester Flowers Jun 1982

Mast Cell Histamine Release Induced By Portuguese Man-Of-War (Physalia) Venom, A. Lester Flowers

Loma Linda University Electronic Theses, Dissertations & Projects

Richet and Portier studied the immunization of dogs against attenuated toxic extracts of the sea anemone and showed that, when given secondary injections of sublethal amounts of native toxic extracts, the dogs experienced severe pruritus and insensitivity followed by death. They called this increased sensitivity to the toxins, anaphylaxis. Richet and Portier, and later Jacques and Schachter, and Uvnäs also studied the direct pruritic and histamine releasing effects of cnidarian (e.g. Physalia, Actinia, Cyanea), toxic extracts. While the anaphylactic effect, discovered by Richet and Portier, has been extended by numerous studies to provide the foundation of our current knowledge of …


The Prairie Naturalist Volume 14, No. 2. June 1982 Jun 1982

The Prairie Naturalist Volume 14, No. 2. June 1982

The Prairie Naturalist

DISTRIBUTIONS, DENSITIES, AND RELATIVE ABUNDANCES OF GRASSHOPPERS (ORTHOPTERA: ACRIDIDAE) IN A NEBRASKA SAND HILLS PRAIRIE ▪ A. Joern

FLORA OF FOREST CLEARINGS CREATED BY LOGGING IN BELTRAMI COUNTY, MINNESOTA ▪ E. W. Devlin

CHRISTMAS BIRD COUNTS FOR NORTH DAKOTA - 1981 ▪ R. N. Randall

RAPTOR USE OF HARDWOOD DRAWS IN CENTRAL NORTH DAKOTA ▪ R. C. Gaines and S. C. Kohn

NOTES ON DUCK NEST STRUCTURES ▪ J. G. Sidle and P. M. Arnold

EFFECT OF SOIL MOISTURE OR SOIL TEMPERATURE ON REPRODUCTION OF INDIGENOUS NEMATODE POPULATIONS IN A MIXED PRAIRIE ▪ J. D. Smolik

CORRECTION: Replacement for Table …


Whole Issue Nebraska Bird Review (June 1982) 50(2). Jun 1982

Whole Issue Nebraska Bird Review (June 1982) 50(2).

Nebraska Bird Review

TABLE OF CONTENTS

The Eighty·first Annual Meeting .................26

A Check-list of the Birds of Mormon Island Crane Meadows .................27

Book Reviews .................36

A Hoary Redpoll in Dodge County .................37

1981 Nebraska Nesting Survey .................38

Possible Evidence of Fish-eating by a Wild Lesser Sandhill Crane from the Central Platte Valley, Nebraska .................42

Wilson Tout, Secretary .................44

Notes .................46