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Articles 50371 - 50400 of 52459
Full-Text Articles in Entire DC Network
Influence Of Nitrogen Fertilization On The Quality And Quantity Of Streamflow From A Forested Watershed, George B. Coltharp, Michael T. Shearer, Everett P. Springer, Robert F. Wittwer
Influence Of Nitrogen Fertilization On The Quality And Quantity Of Streamflow From A Forested Watershed, George B. Coltharp, Michael T. Shearer, Everett P. Springer, Robert F. Wittwer
KWRRI Research Reports
This project was designed to determine the effects of nitrogen fertilization on the quality and quantity of streamflow eminating from an eastern hardwood forest watershed. A 40.67 ha watershed, located in mountainous eastern Kentucky, was aerially fertilized in late April 1975. The forest stand was principally oak, hickory, and yellow poplar, 50 - 55 years of age and in a relatively undisturbed condition. A helicopter applied anunonium nitrate at a rate of 504 kg/ha. Because a large part of applied nitrogen fertilizer ends up in the highly mobile nitrate nitrogen.form, this is the principal ion monitored in this study. No …
Attributes Of The Deer Hunting Experience: A Cluster-Analytic Study, Jacob Hautaluoma, Perry J. Brown
Attributes Of The Deer Hunting Experience: A Cluster-Analytic Study, Jacob Hautaluoma, Perry J. Brown
Forest Management Faculty Publications
Using data from Washington State deer hunters, this paper reports on a cluster analytic study of the attributes of the deer hunting experience. The data were collected by mail questionnaire from 3,924 deer hunters by Potter, Hendee, and Clark (1973). Scaled data were subjected to a variable cluster analysis, and then variable clusters were used in an object cluster analysis of hunters. Several dimensions of the deer hunting experience which add to or detract from satisfaction, and groups of hunters reacting differently to these dimensions, are identified. Nature, harvest, equipment, out-group contact, and skill are identified as important attributes of …
State Of The Fisheries Report 1977, Department Of Fisheries And Wildlife, Western Australia
State Of The Fisheries Report 1977, Department Of Fisheries And Wildlife, Western Australia
Status Reports of the Fisheries and Aquatic Resources
The total value of the fisheries of Western Australia is the highest of any of the States, and the Western Australian rock lobster fishery is the most valuable single fishery in Australia.
The Prairie Naturalist Vol. 10, No. 3. September 1978
The Prairie Naturalist Vol. 10, No. 3. September 1978
The Prairie Naturalist
NOTES ON DISTRIBUTION OF THREE SPECIES OF MAMMALS IN SOUTH DAKOTA ▪ J. K. Jones, Jr., J. R. Choate and R. B. Wilhelm
A MID-CONTINENT IRRUPTION OF CANADA LYNX, 1962-63 ▪ H. L. Gunderson
CHECKLIST OF NORTH DAKOTA MAMMALS (REVISED) ▪ J. M. Wiebe and J. F. Cassel
DECLINE OF YEAR-CLASS STRENGTH OF BUFFALO FISHES IN LAKE SAKAKAWEA, NORTH DAKOTA ▪ D. W. Willis and J. B. Owen
NOTE
Pileated Woodpecker Eating Russian Olive Fruits ▪ R. S. McVoy
BOOK REVIEWS
Birds of the Prairie Provinces ▪ W. J. Maher
Wildlife of the Prairies ▪ C. R. Grondahl
Distribution Patterns …
Lactate Dehydrogenase Isozyme Patterns From Five Species Of Snakes : Comparison Of Rattlesnake Vibratory Muscle With Body Epaxial Muscle, Cecil Bernard Cross
Lactate Dehydrogenase Isozyme Patterns From Five Species Of Snakes : Comparison Of Rattlesnake Vibratory Muscle With Body Epaxial Muscle, Cecil Bernard Cross
Master's Theses
Lactate dehydrogenase (LDH) isozyme patterns of seven tissues in each of five species of snakes are described from their polyacrylamide gel electrophoretic characteristics. The tissues examined included vibratory tail muscle, non vibratory tail muscle, body epaxial muscle, heart muscle, whole blood, liver and kidney. The species of snakes included Crotalus adamanteus, C. h. horridus, Agkistrodon piscivorus and Sistrurus miliarius barbouri from the family Crotalidae and Natrix taxispilota from the family Colubridae. These snakes show a decreasing continuum of tail vibratory activity, respectively, to N. taxispilota, which has a nonvibratory tail muscle.
Crotalus adamanteus, C. h. horridus and A. piscivorus have …
Mercury, Copper, And Zinc In Selected Ichthyofauna Of Lower Chesapeake Bay And Hampton Roads, Virginia, W. Bruce Aitenhead
Mercury, Copper, And Zinc In Selected Ichthyofauna Of Lower Chesapeake Bay And Hampton Roads, Virginia, W. Bruce Aitenhead
OES Theses and Dissertations
Anchovys, croaker, spat, summer flounder and hogchokers were collected monthly to seasonally from November 1972 to October 1973 at three locations in the southern Chesapeake Bay region of Virginia.
The concentrations of mercury, copper and zinc were determined by atomic absorption spectrophotometry in whole fishes. Metal concentration varied with species and location. Anchovys had the highest mean concentrations of mercury and zinc while hog- chokers had the highest mean copper concentration. Mercury levels exceeding O.5 ppm were observed in species from all three loca- tions, but maximum heavy metal concentrations per species were highest in Craney Island fishes.
Temporal variations …
"Toxic Chemicals In The Environment", William E. Cooper
"Toxic Chemicals In The Environment", William E. Cooper
Special Collections: Oregon Public Speakers
Presented and recorded with Arbib, M. A., "Environmental Simulation and Long-Term Planning."
The Kinetics Of Solvent Reorientation In Hydroxylated Solvents From The Exciting-Wavelength Dependence Of Chromophore Emission Spectra, John Milton, Robert M. Purkey, William C. Galley
The Kinetics Of Solvent Reorientation In Hydroxylated Solvents From The Exciting-Wavelength Dependence Of Chromophore Emission Spectra, John Milton, Robert M. Purkey, William C. Galley
WM Keck Science Faculty Papers
The disappearance of the exciting-wavelength dependence of the phosphorescence spectra of polar, aromatic chromophores in supercooled glycol–water mixtures is utilized to monitor the kinetics of solvent reorientation. Reorientation times in the nanosecond to second range are obtained for (3:2 v/v) glycerol–water and (1:1 v/v) ethylene glycol–water at 140–240 °K. The results suggest that the process is one involving a cluster of solvent molecules and in which the chromophore plays a relatively passive role. Steady-state data and direct measurements of phosphorescence shifts as a function of time indicate that the solvent reorientation process is nonexponential in nature. The decay function derived …
The Prairie Naturalist Vol. 10, No. 2. June 1978
The Prairie Naturalist Vol. 10, No. 2. June 1978
The Prairie Naturalist
ANALYSIS OF THE FLEHMEN DISPLAY IN AMERICAN BISON (BISON BISON) ▪ B. R. Mahan, M. P. Munger and H. L. Gunderson
AVIAN MORTALITY CAUSED BY A SEPTEMBER WIND AND. HAIL STORM ▪ K. F. Higgins and M. A. Johnson
DISTRIBUTION OF TWO SPECIES OF LONG-EARED BATS OF THE GENUS MYOTIS ON THE NORTHERN GREAT PLAINS ▪ J. K. Jones, Jr. and J. R. Choate
ALFALFA AND THE OCCURRENCE OF FISSURES ON THE NORTH DAKOTA PRAIRIES ▪ J. P. Bluemle, A. E Kehew, E. A. Brostuen and K. L. Harris
NOTES
An Observation of Badger Predation on Richardson Ground Squirrels ▪ …
Influence Of Denervation And Hemithyroidectomy On The Age Related Increase In The Number Of Calcitonin-Containing Cells In Mouse Thyroid, Nualnoi Wechbanjong
Influence Of Denervation And Hemithyroidectomy On The Age Related Increase In The Number Of Calcitonin-Containing Cells In Mouse Thyroid, Nualnoi Wechbanjong
Loma Linda University Electronic Theses, Dissertations & Projects
It has been concluded from this study that nerve fibers in the superior laryngeal nerves have an influence on the development of C-cells in the mouse thyroid. This conclusion is based on the results of two types of investigation. The first is an analysis of the effect of age on the number of C-cells and the second is an investigation of the influence of denervation and hemithyroid-parathyroidectomy on the age related changes in C-cells numbers.
I. The distribution and c011centraticn of C-cells in mouse thyroid at various ages.
Serial 6 µm sections of thyroid glands from Swjss Webster mice at …
The Use Of Rat Liver Cell Cultures For The Isolation Of Histoplasma Capsulatum Darling, Allen Robert Riebau
The Use Of Rat Liver Cell Cultures For The Isolation Of Histoplasma Capsulatum Darling, Allen Robert Riebau
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 by Allen Robert Riebau on May 12, 1978.
Requirement For Protein Synthesis In Adrenocorticotropin Stimulated Steroidogenesis Of Isolated Rat Adrenal Cells, John G. Menke
Requirement For Protein Synthesis In Adrenocorticotropin Stimulated Steroidogenesis Of Isolated Rat Adrenal Cells, John G. Menke
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 John G. Menke on May 6, 1978.
Kentucky Warbler (Vol. 54, No. 2), Kentucky Library Research Collections
Kentucky Warbler (Vol. 54, No. 2), Kentucky Library Research Collections
The Kentucky Warbler
No abstract provided.
A Discriminant Function Model Of Gray-Headed Junco Habitat, Andrew R. Grainger
A Discriminant Function Model Of Gray-Headed Junco Habitat, Andrew R. Grainger
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This paper presents a description of gray-headed junco habitat in the form of a model based on discriminant function analysis. Junco nests were found by searching randomly located grids on a 7.8 km2 study area in central Utah. Vegetation data was gathered on 500 m2 circular plots surrounding nests and contrasted with similar data from searched grids where nests were not found. The model explains 28 percent of the between-groups variance and correctly classifies 68 percent of the plots.
Plant cover types are good predictors of areas where gray-headed juncos nest, while plant community type descriptions do not …
Conflict In Outdoor Recreation, Gerald R. Jacob
Conflict In Outdoor Recreation, Gerald R. Jacob
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The causes of conflict among users of outdoor recreation resources have received little attention from recreation researchers. Knowledge of factors responsible for conflict might assist recreation planners' attempts to reduce future instances of conflict and help management focus its conflict resolution efforts. A theory of conflict is offered as the first step in systematically procuring such knowledge. A definition and characteristics of outdoor recreation conflicts are presented; four comprehensive causes of user conflicts are proposed. Ten propositions are used to link these factors to conflict and suggest future research hypotheses. The social psychological dynamics of conflict, as described here, have …
Adaptive Significance Of Lactate Dehydrogenase B2 Isozymes In Rainbow Trout, Salmo Gairdneri And A Biochemical Genetic Comparison Of Cutthroat Trout (Salmo Clarki) Populations, Gerald Thomas Klar
Adaptive Significance Of Lactate Dehydrogenase B2 Isozymes In Rainbow Trout, Salmo Gairdneri And A Biochemical Genetic Comparison Of Cutthroat Trout (Salmo Clarki) Populations, Gerald Thomas Klar
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Rainbow trout lactate dehydrogenase (LDH) B2' B2' , B2' B2" and B2" B2" phenotypes were tested under a variety of conditions for swimming endurance, oxygen consumption rates, and blood pH, pO2, and lactate. The B2" B2" phenotype exhibited a lower swimming endurance, under a limited oxygen supply, than the B2' B2' and B2' B2" phenotypes. Blood pH at fatigue did not differ among the LOH phenotypes that swam under low oxygen conditions (2 mg/1). …
Plant Succession Studies On Subalpine Acid Mine Spoils In The Beartooth Mountains, Patricia Lea Howard
Plant Succession Studies On Subalpine Acid Mine Spoils In The Beartooth Mountains, Patricia Lea Howard
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Large areas within alpine and subalpine tundra have been by disturbed by mining during this century. The most promising method for retarding deterioration of these areas is revegetation with native species through both seeding and transplants. One natural process of revegetation which occurs on portions of many existing disturbances seems to be the establishment of a few species that expand with time to form matts of plants.
At the McLaren Mine, located at 3000 m elevation in the Beartooth Mountains, Montana, active succession is occurring and is dominated by Carex species. Seed viability and successional patterns studies were conducted on …
Physiological Response To Hooking Stress In Largemouth Bass (Micropterus Salmoides), A. Wayne Gustaveson
Physiological Response To Hooking Stress In Largemouth Bass (Micropterus Salmoides), A. Wayne Gustaveson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Recent concern about large initial and delayed mortalities resulting from tournament angling for largemouth bass has indicated that it would be desirable to further evaluate the fate of fish that are released after being captured by angling. This study was designed to evaluate sublethal physiological disruptions caused by hooking stress after largemouth bass were played under standardized conditions (0-5 minutes) and to estimate the time needed for recovery of the homeostatic mechanisms (to 72 hours). Blood lactate was used as a measure of metabolic fatigue; plasma osmolality and chloride measurements were used to evaluate osmoregulatory disturbances and gill ion-exchange; and …
The Combined Effects Of Air Temperature, Wind, And Radiation On The Resting Metabolism Of Avian Raptors, Steven R. Hayes
The Combined Effects Of Air Temperature, Wind, And Radiation On The Resting Metabolism Of Avian Raptors, Steven R. Hayes
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
American kestrels, Falco sparverius; red-tailed hawks, Buteo jamaicensis; and golden eagles, Aguila chrysaetos, were perched in a wind tunnel and subjected to various combinations of air temperature, wind, and radiation. Oxygen consumption was measured under the various combinations of environmental variables, and multiple regression equations were developed to predict resting metabolism as a function of body mass, air temperature, wind speed, and radiation load. Heat transfer analysis of the bird-thermal environment relationship was conducted to produce a biophysical model describing resting metabolism as a function of feather thermal conductance.
Because of differences in surface area to mass …
Interregional Competition In Markets Facing Utah Livestock And Poultry Producers, Terrell O. Sorensen
Interregional Competition In Markets Facing Utah Livestock And Poultry Producers, Terrell O. Sorensen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this thesis is to make an evaluation of the competitive position of the Utah livestock industry based on feed ingredient and transportation costs, This is done by the use of a linear programming model (MPS-360). This is on the basis of the least cost means of production to meet the quantity demanded of the livestock products. This is accomplished by dividing the United States into six regions where Utah is one of these regions to enable careful consideration of Utah's agricultural enterprises.
Beef, pork, broilers, turkeys, eggs, and milk are the agricultural products used in the model. …
The Effect Of Selenium On The Toxicity Of Methyl Mercury In Medaka Embryos, Peter H. Krauth
The Effect Of Selenium On The Toxicity Of Methyl Mercury In Medaka Embryos, Peter H. Krauth
All-Inclusive List of Electronic Theses and Dissertations
The purpose of this research was to investigate the effect of selenium upon methyl mercury poisoning in Medaka fish (Oryzias latipes) embryos. Selenium has been shown to provide a protective mechanism against mercury poisoning in some adult animals. Three experiments were done. In the first, selenium and methyl mercury were put directly in the growing medium of the eggs. In the second experiment, selenium was included in the diet of the parent fish. In the third part, methyl mercury exposure was delayed three days. The results of the first experiment were quite dramatic and showed a significant difference when selenium …
Population Dynamics And Net Production Of Brown Trout (Salmo Trutta) In Two Areas Of A High Gradient Mountain Stream, Jeffrey C. Gosse
Population Dynamics And Net Production Of Brown Trout (Salmo Trutta) In Two Areas Of A High Gradient Mountain Stream, Jeffrey C. Gosse
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Estimates of the brown trout (Salmo trutta) population were made in two areas of the Blacksmith Fork River, Cache County, Utah, from June 1972 to June 1973. Additional data were obtained on movement, growth, mortality, biomass, production, and yield.
Population density was highly variable in the area where habitat alterations had occurred, but was relatively uniform where the habitat was undisturbed. The brown trout exhibited little movement except during spawning season. Instantaneous growth and mortality rates are provided for each age group.
Mean annual biomass in the two areas was 12.0 and 10.2 grams per square meter and …
Feeding Habits And Reproduction Of Three Sympatric Lizard Species From West-Central Utah, John B. Andre
Feeding Habits And Reproduction Of Three Sympatric Lizard Species From West-Central Utah, John B. Andre
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The feeding habits and reproduction of Uta stansburiana, Crotaphytus collaris and Cnemidophorus tigris during spring and summer 1976 are described. Feeding habits are expressed in percent total number and volume of prey items and frequency of occurrence of each prey category. Importance Values are also calculated. These values better illustrate the feeding habits of the lizard species than either percent total number and volume and frequency of prey category occurrence.
Lizards consume a variety of food items throughout the growing season. Hymenoptera, Coleoptera, Orthoptera and Arachnida are the major prey categories of U. stansburiana. The major prey categories …
The Effect Of Architectural Variation In Habitat On A Spider Community: An Experimental Field Study -- With Special Reference To Resource Partitioning, James Vincent Robinson
The Effect Of Architectural Variation In Habitat On A Spider Community: An Experimental Field Study -- With Special Reference To Resource Partitioning, James Vincent Robinson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Spider community acceptance of, and segregation by, architectural configuration was investigated for the spiders of Green Canyon in northern Utah. Modular habitat units consisting of 30.48 centimeter (1 foot) cubes of chicken wire supporting internal strands of macrame jute tied in different orthogonal configurations were used. Configurations including all three axes were tested at two strand densities.
The primary null hypothesis tested, that spider species use structures independent of architecture, was rejected in favor of the alternate hypothesis that spider species differentially use structures dependent upon architecture. Of the eight most abundant species, two showed preferences for horizontal substrata and …
Analysis Of Ecosystem Models, Walter Dewey Valentine
Analysis Of Ecosystem Models, Walter Dewey Valentine
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Recent attempts to apply frequency response analysis to compartmental models of ecosystems are flawed by the failure to define terms in an unambiguous and ecologically meaningful way, and by the failure to distinguish between information feedback and closed material loops. Analysis of the sensitivity of linear models to changes in the A matrix has shortcomings too: elements of the A matrix are often derived from more fundamental parameters and thus do not have a direct relationship to the parent model; only sensitivities to the fundamental parameters will be unconfounded and readily interpretable. A more serious problem with these techniques is …
Abstracts Of Contributed Papers, Iowa Academy Of Science [90th Meeting], April 21-22, 1978, Iowa Academy Of Science
Abstracts Of Contributed Papers, Iowa Academy Of Science [90th Meeting], April 21-22, 1978, Iowa Academy Of Science
Iowa Academy of Science Documents
Presentation abstracts from the annual meeting of the Iowa Academy of Science
The Annual Meeting Of The Iowa Academy Of Science April 21-22, 1978 [Program, 90th Meeting], Iowa Academy Of Science
The Annual Meeting Of The Iowa Academy Of Science April 21-22, 1978 [Program, 90th Meeting], Iowa Academy Of Science
Iowa Academy of Science Documents
No abstract provided.
Development Of A Testing Procedure For Gloss Ink Holdout, Steven M. Cunningham
Development Of A Testing Procedure For Gloss Ink Holdout, Steven M. Cunningham
Paper Engineering Senior Theses
There is currently no standard acceptable method used to evaluate gloss ink holdout. Four methods are investigated to evaluate holdout. Heat seat ink is used to reduce absorption effects. The K&N ink smear test and the Vanceometer absorption tester are both discounted as inappropriate tests since they look at absorption alone and have widely varied results. The IGT printability tester is an improvement because it involves another major influence to holdout, printing pressure, but does not hold the ink film thickness constant. The Vandercook Proof Press procedure is judged the most valuable since it takes into account printing pressure and …
The Effects Of Polymer Molecular Weight On Colloidal Retention And The Bridging Mechanism, Joseph A. Bergeron
The Effects Of Polymer Molecular Weight On Colloidal Retention And The Bridging Mechanism, Joseph A. Bergeron
Paper Engineering Senior Theses
A review of retention is presented. Included are discussions concerning retention mechanisms, variables which affect retention, variables affected by retention and various retention aids. A detailed experimental procedures involving the use of the dynamic retention/drainage jar is included along with several modifications of the apparatus.
The purpose of the experimental work was to study the effects of polymer molecular weight on retention and the bridging mechanism. Two cationic retention aids of low and high molecular weight along with two non-ionic "bridging agent" retention aids were employed. Various combinations of these chemicals were studied at different levels of addition and under …
The Effect Of Carbon Black On Tr Moisture Measurements And Beta Ray Basis Weight Measurements, William A. Beck
The Effect Of Carbon Black On Tr Moisture Measurements And Beta Ray Basis Weight Measurements, William A. Beck
Paper Engineering Senior Theses
Computer control of paper industry processes is becoming a very significant segment of the industry. Of major importance is on-line measurement and control of moisture and basis weight in the web, those two parameters affect practically every other sheet characteristics. Accurate closed loop control is essential to keeping the product within customer-demanded specifications.
Board mills in particular utilize large quantities of waste paper, with the rate of usage expected to increase from 20.5 percent in 1970 to 26 percent by 1985. The concentration of contaminants will increase at a similar rate. One such contaminant, carbon black, will reduce the effectiveness …