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Articles 1081 - 1110 of 1435
Full-Text Articles in Physical Sciences and Mathematics
Petrology Of The Arumbera Sandstone, Late Proterozoic(?) - Early Cambrian, Northeastern Amadeus Basin, Central Australia, Keith T. Conrad
Petrology Of The Arumbera Sandstone, Late Proterozoic(?) - Early Cambrian, Northeastern Amadeus Basin, Central Australia, Keith T. Conrad
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Arumbera Sandstone forms distinctive strike ridges with dark reddish slopes and orange-white cliffs throughout most of the northeastern Amadeus Basin. It is divisible into four readily mappable informal units. The ridge-forming units, 2 and 4, are divided into three and two subunits, respectively.
Unit 1, Subunit 2b, Unit 3 and Subunit 4b are generally comprised of recessive, pale-red to grayish-red, medium- to thin-bedded, fineto medium-grained arkose with major proportions of siltstone and mudshale. These sedimentary bodies are interpreted as a complex system of coastal to nearshore-marine environments including tidal flats, tidal channels, estuaries and beaches. Evidence includes: (1) predominance …
Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek
Petrology Of The Middle Cambrian Blacksmith Formation, Southeastern Idaho And Northernmost Utah, David Paul Zelazek
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Blacksmith Formation of Middle Cambrian (Albertan) age was studied in southeastern Idaho and northernmost Utah. Lithology and sedimentary structures were compared with modern environments and ancient rocks to determine environments of deposition, paleo-geography, diagenetic alterations and patterns of dolomitization.
The Blacksmith Formation can be divided into five basic rock types. Rock type A has cryptalgalaminae, mudcracks, and lacks bioturbation. Rock type A is inferred to have been deposited in the upper intertidal to supratidal environment. Rock type B is extremely dolomitized and brecciated. It is inferred that rock type B was deposited in the upper intertidal to supratidal environment. …
Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines
Faunal Succession And Depositional Environments Within The Lodgepole Limestone (Early Mississippian) Of Samaria Mountain, Idaho, Gary Keith Hines
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Community succession, the orderly changes a community experiences with time, is considered to be the result of either autogenic or allogenic factors working singularly or in combination. It has been further suggested that, as communities undergo succession, certain biological parameters change in a predictable manner. Examination of members 2 through 4 of the Mississippian (Kinderhook-Osage) Lodgepole Formation of Samaria Mountain, Idaho provides a means to evaluate these concepts.
Within the study section comprised of 125 beds (61.5 m thick), four rock types are recognized. These include: (1) fossiliferous wackestone (78% of beds), which ranges in color from dark-gray (N3) to …
Comparison Of Toxicological Models For Evaluation Of Air Pollutants: Response Of The Pulmonary Alveolar Macrophage To Hexavalent Chromium, Jennifer Baker Galvin
Comparison Of Toxicological Models For Evaluation Of Air Pollutants: Response Of The Pulmonary Alveolar Macrophage To Hexavalent Chromium, Jennifer Baker Galvin
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This study was designed to accomplish two primary objectives: (1) to compare two test methods commonly used to evaluate toxicity of inhaled air pollutants, and (2) to observe the response as measured by each of the methods, of pulmonary alveolar macrophages exposed to 2μg hexavalent chromium.
The first method evaluated featured use of intratracheal injections to simulate live inhalation exposures, and the second required exposure of macrophages cultured on petri plates. Pulmonary alveolar macrophages harvested from Long Evans rats were used. The two cell function parameters measured in the evaluations were chemiluminescence and oxygen consumption (which was determined for cells …
Mineralogy And Petrology Of Lava Flows (Tertiary-Quaternary) In Southeastern Idaho And At Black Mountain, Rich County, Utah, Barbara J. Puchy
Mineralogy And Petrology Of Lava Flows (Tertiary-Quaternary) In Southeastern Idaho And At Black Mountain, Rich County, Utah, Barbara J. Puchy
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Lava flows of Tertiary-Quaternary age occur in Enoch Valley, Upper Valley, and Slug Valley in southeastern Idaho. The basalts in Upper Valley and Enoch Valley contain olivine (Fo69 to Fo37), plagioclase (An62 to An39), augite and Fe-Ti oxides. The lava in Slug Valley lacks plagioclase, but contains sanidine (Or70 to Or56) with a trace of biotite and amphibole, and thus, has been termed alkali trachyte.
Black Mountain, on the eastern side of Bear Lake, northeastern Utah, is capped by basalt. Minerals present include olivine (Fo83 to Fo72), plagioclase …
Explanation Of The Fast Fourier Transform And Some Applications, Alan Kazuo Endo
Explanation Of The Fast Fourier Transform And Some Applications, Alan Kazuo Endo
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This report describes the Fast Fourier Transform and some of its applications. It describes the continuous Fourier transform and some of its properties. Finally, it describes the Fast Fourier Transform and its applications to hurricane risk analysis, ocean wave analysis, and hydrology.
Resource Partitioning In Breeding Populations Of Marsh Hawks And Short-Eared Owls, Susan C. Linner
Resource Partitioning In Breeding Populations Of Marsh Hawks And Short-Eared Owls, Susan C. Linner
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
During the 1979 breeding season four pairs of northern harriers, or marsh hawks (Circus cyaneus) and four pairs of short-eared owls (Asio flammeus) were studied in Cache Valley, Utah. The study was concerned solely with diurnal resource utilization, and did not examine the owls' nocturnal activities. The home range of each harrier pair overlapped substantially with that of an owl pair. Percent habitat overlap for hawk-owl pairs varied from 39 percent to 72 percent. Observations were made to determine if differences existed in their utilization of habitat and food resources, or in their daily and seasonal …
Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire
Effects Of Host Plant Patch Size And Surrounding Plant Type On Insect Population Dynamics, Lynn A. Maguire
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of the present study was to investigate how plant spatial patterns and insect behavior interact to influence the population dynamics of insects using the plants. The study included three phases: l) field experiments using collards (Brassica oleracea) and the crucifer insect fauna; 2) simulation models representing the population dynamics of an insect herbivore as functions of insect dispersal behavior and host plant patch size; and 3) model-field syntheses integrating model predictions and field variability estimates to choose an appropriate spatial scale for future field experiments or applications.
In field experiments on surrounding plant type, collards were …
Chlorophyll Fluorescence Probe Of Ultraviolet-B Photoinhibition Of Primary Photoreactions In Intact Leaves, Robert S. Nowak
Chlorophyll Fluorescence Probe Of Ultraviolet-B Photoinhibition Of Primary Photoreactions In Intact Leaves, Robert S. Nowak
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Damage to primary photosynthetic reactions caused by environmental stress can be assessed by measurement of chlorophyll fluorescence induction in intact leaves. This approach was applied in studies of ultraviolet-B photoinhibition of photosynthesis in Pisum sativum L. and Rumex patientia L. leaves. At ultraviolet-B dose rates insufficient to cause inhibition of net photosynthesis, changes in the magnitude of fluorescence transients did occur, which suggested direct effects on chloroplast pigments in Pisum and inhibition of photosynthetic electron transport between the photosystems in both species. Leaves of these two species subjected to a much higher dose rate had a significant reduction of net …
Production Of Mountain Whitefish (Prosopium Williamsoni) In Altered And Unaltered Reaches Of Two Intermountain Streams In Their Alluvial Flood Plains, Michael J. Ottenbacher
Production Of Mountain Whitefish (Prosopium Williamsoni) In Altered And Unaltered Reaches Of Two Intermountain Streams In Their Alluvial Flood Plains, Michael J. Ottenbacher
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Estimates of production and related parameters (growth rate, density, standing crop) were made for populations of mountain whitefish in altered and "unaltered" areas of the Blacksmith Fork and Logan River, Utah from spring 1975 through summer 1976. Capture records of marked whitefish were also analyzed to describe fish movement and check on assumptions implicit in the population estimator.
Mean weights and instantaneous growth rates of whitefish were similar at all sites for comparable size/age groups. Among sites, differences in production per sampling interval and annual production were due mainly to differences in standing crop and/or age structure.
Estimates of mountain …
Relationship Between Rainfall And Storm Runoff For Selected Arizona Watersheds, Robert James Anderson
Relationship Between Rainfall And Storm Runoff For Selected Arizona Watersheds, Robert James Anderson
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The relationship between rainfall and runoff was examined for twelve selected Arizona watersheds. Expedient runoff volume model coefficients and runoff curve number model parameters were examined using standardized structure, with modifications to adjust the model for small initial abstractions and large watershed storage capacity.
Forest-land management practices were examined for their effects on curve number coefficients. The effects of rainfall characteristics were also evaluated with respect to changes they induce in curve number populations.
Evaluations included a runoff fraction, a simple multiplier of storm volume to produce runoff volume. The accuracy of this model is promising for more permeable watersheds.
Characteristics And Genesis Of Certain Soils In The Southern Foothills Of Central Alborz, Iran, Firouz Rooyani
Characteristics And Genesis Of Certain Soils In The Southern Foothills Of Central Alborz, Iran, Firouz Rooyani
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Characteristics and genesis of five pedons representing some of the soils of the central Alborz mountain northeast of Tehran were investigated. The present climate of the area is similar to the Mediterranean climate. The parent materials for the soils under study have apparently been derived from the Ecocene Alborz Green Beds (a thinly bedded light green mudstone), the Pliocene Hezardareh Formation (a poorly-cemented conglomerate) and Recent alluvium and colluvium. Pedons 2 and 4 are located at lower elevations (plain and river terraces) on 1 to 2 percent slopes. Pedons 3 and 5 are located at higher elevations (hills that surround …
Structure And Petrology Of Tertiary Volcanic Rocks Near Etna, Utah, Kent W. Smith
Structure And Petrology Of Tertiary Volcanic Rocks Near Etna, Utah, Kent W. Smith
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Three volcanic domes and related volcanic rocks of Tertiary age are located near Etna, Utah, in Box Elder County. The domes follow a north-south trend and are fault controlled. Flow structure indicates a change from a less viscous, flow-forming lava which produced an exogenous dome to a more viscous lava which formed endogenous domes. Associated pyroclastic deposits are negligible. The volcanic rocks are composed of porphyritic rhyolite and rhyolitic vitrophyre having phenocrysts of quartz, sanidine, plagioclase and biotite with minor amounts of Fe-Ti oxides, hypersthene, allanite and calcic amphibole. Quartz and sanidine phenocrysts are generally embayed whereas plagioclase phenocrysts are …
Effects Of Pesticides On Immune Competency: Influence Of Methyl Parathion And Carbofuran On Immunologic Responses To Salmonella Typhimurium Infection, Anna M. Fan
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Immunologic competence is correlated with resistance to infectious disease which may be affected by exposure to certain compounds. Methyl parathion (MP) and carbofuran (CF) have been reported to affect the development of active immunity in the rabbit and the present research was conducted to quantify the dosage relationships of these two pesticides to both host resistance and acquired resistance in the mouse.
Preliminary study was made on the virulence of Salmonella typhimurium in mice. Mortality rates among infected animals fed Purina Laboratory Chow diet providing 0.08, 0.7 3.0 mg MP/kg/day or 0.1, 0.6, 1.0 mg CF/kg/day along with untreated controls …
Growth, Morphology, Habit And Habitat Of Selected Brachiopod And Mollusc Species From The Meade Peak Member Of The Phosphoria Formation, Permian, Northeastern Utah - Southeastern Idaho - Southwestern Wyoming, Scott Lewis Russell
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The Permian Meade Peak Member of the Phosphoria Formation was examined at four localities in this investigation. Fossils were collected at each locality. The four collecting localities visited in this investigation are: Brazier Canyon, Utah, Montpelier Canyon, Idaho, Coal Canyon, Wyoming, and Cokeville, Wyoming.
The environment of deposition of the Meade Peak Member in the study area is inferred to have been an outer shelf or basin characterized by moderately deep and quiet water. This has aided reconstruction of life habits, population dynamics, and growth characteristics of the examined species.
The articulate brachiopod Leiorhynchoidea weeksi is inferred to have attached …
Geology, Characteristics, And Resource Potential Of The Low Temperature Geothermal System Near Midway, Wasatch County, Utah, James F. Kohler
Geology, Characteristics, And Resource Potential Of The Low Temperature Geothermal System Near Midway, Wasatch County, Utah, James F. Kohler
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Recent awareness of the finite nature of fossil-fuel resources has resulted in an increased interest in alternate sources of energy such as geothermal. To evaluate the geothermal energy potential of the hot-springs system near Midway, Wasatch Co., Utah, consideration was given to heat flow, water chemistry, and structural controls.
Abnormal heat flow was indicated qualitatively by snow-melt patterns and quantitatively by heat-flow measurements that were obtained from two of four temperature-gradient wells drilled in the area. These measurements indicated that the area north of the town of Midway is characterized by heat flow equal to 321.75 mW/m2, which …
A Confidence Interval Estimate Of Percentile, How Coung Jou
A Confidence Interval Estimate Of Percentile, How Coung Jou
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The confidence interval estimate of percentile and its applications were studied. The three methods of estimating a confidence interval were introduced. Some properties of order statistics were reviewed. The Monte Carlo Method -- used to estimate the confidence interval was the most important one among the three methods. The generation of ordered random variables and the estimation of parameters were discussed clearly. The comparison of the three methods showed that the Monte Carlo method would always work, but the K-S and the simplified methods would not.
Exact Analysis Of Variance With Unequal Variances, Noriaki Yanagi
Exact Analysis Of Variance With Unequal Variances, Noriaki Yanagi
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this paper was to present the exact analysis of variance with unequal variances. Bishop presented the new procedure for the r-way layout ANOVA. In this paper, one and two way layout ANOVA were explained and Bishop's method and Standard method were compared by using a Monte Carlo method.
Evaluation Of Multivariate Homogenous Arma Model, Lucy Chienhua Tseng
Evaluation Of Multivariate Homogenous Arma Model, Lucy Chienhua Tseng
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The purpose of this thesis is to study a restricted multivariate AFRMA model, called the Homogeneous Model. This model is defined as one in which each univariate component of the multivariate model is of the same order in p and q as it is in the multivariate model.
From a mathematical respect, multivariate ARMA model is homogeneous if, and only if, its coefficient matrices are diagonal. From a physical respect, the present observation of a phenomenon can be modeled only by its own past observation and its present and past "errors."
The estimation procedures are developed based on maximum likelihood …
Determining Initial Values For Stiff Systems With Incomplete Initial Data, Yech-Kuang Ning
Determining Initial Values For Stiff Systems With Incomplete Initial Data, Yech-Kuang Ning
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Stiff differential equations frequently arise in physical problems due to the existence of greatly differing time constants. One way of solving stiff differential equations is taking the step size very small, another way is using an A-stable or stiffly stable implicit method. The purpose of this thesis is to discuss the method of determining initial values for stiff systems. The algorithm was motivated by a problem from ionospheric physics in which some of the initial values are unknown. If we give those unknown initial values an arbitrary number and integrated with those values, we have an initial transient. However, if …
Extreme Value Distribution In Hydrology, Bill (Tzeng-Lwen) Chen
Extreme Value Distribution In Hydrology, Bill (Tzeng-Lwen) Chen
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The problems encountered when empirical fit is used as the sole criterion for choosing a distribution to represent annual flood data are discussed. Some theoretical direction is needed for this choice. Extreme value theory is established as a viable tool for analyzing annual flood data. Extreme value distributions have been used in previous analyses of flood data. However, no systematic investigation of the theory has previously been applied. Properties of the extreme value distributions are examined. The most appropriate distribution for flood data has not previously been fit to such data. The fit of the chosen extreme value distribution compares …
Some Effects Of A Grazer, Hyalella Azteca On Ecosystem Level Properties In Aquatic Microcosms, Martin D. Werner
Some Effects Of A Grazer, Hyalella Azteca On Ecosystem Level Properties In Aquatic Microcosms, Martin D. Werner
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A study to determine some ecosystem level effects of an aquatic invertebrate grazer, Hyalella azteca, was performed in aquatic ix microcosms. Impact of the grazer was assessed in three general areas: 1) inorganic nutrient levels of the microcosm water column, 2) productivity and respiration of the biotic community, and 3) plant community composition in the microcosms.
The grazing amphipod caused inorganic phosphorus and nitrogen (except ammonia) levels to be elevated in the microcosms. The increase was due, at least partially, to excretion of nutrients into the water by the amphipod. The presence of H. azteca did not significantly …
A Μ-Model Approach On The Cell Means: The Analysis Of Full, Design Models With Non-Orthogonal Data, Richard Van Koningsveld
A Μ-Model Approach On The Cell Means: The Analysis Of Full, Design Models With Non-Orthogonal Data, Richard Van Koningsveld
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This work considers the application of a µ-model approach on the cell means to a special yet important class of experimental designs. These include full factorial, completely nested, and mixed models with one or more observations per cell. By limiting attention to full models, an approach to the general data situation is developed which is both conceptually simple and computationally advantageous.
Conceptually, the method is simple because the design related effects are defined as if the cell means are single observations. This leads to a rather simple algorithm for generating main effect contrasts, from which associated interaction contrasts can also …
Spectral Signature Studies For Application In Deer Census Using Remote Sensing Techniques, Maran C. Pate
Spectral Signature Studies For Application In Deer Census Using Remote Sensing Techniques, Maran C. Pate
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
This study was performed to determine the spectral signatures of deer and their natural background elements for censusing purposes. Consideration was given to atmospheric transmittance, acceptable flying weather, and terrain. Possible spectral bands between 0.3 and 14.0 μm were obtained (over a pathlength of 1500 feet at an altitude of 5000 feet) based upon atmospheric transmittance using the LOWTRAN 3B computer program. They are: 0.30 - 1.33, 1.49 - 1.79, 2.00 - 2.50, 3.00 - 3.16, 3.38 - 4.10, 4.59 - 5.05, and 8.00 - 13.33 μm, for transmittance greater than 75%. Weather conditions are favorable for flying and taking …
Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick
Biology, Reproductive Potential And The Impact Of Fishing Pressure On The Bluegill Fishery Of Pelican Lake, Uintah County, Utah, Bob D. Burdick
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Certain aspects of the biology of two species of fish, bluegill (Lepomis macrochirus) and largemouth bass (Micropterus salmoides), and the assessment of fishing pressure upon the sport fishery of Pelican Lake, Uintah County, Utah, a 680 ha warmwater lake, were studied between April 1, 1976 and June 30, 1978. The growth rate of bluegills (sexes combined) was fairly rapid; the mean back-calculated total lengths from ages one through nine were 55, 112, 166, 194, 211, 229, 245, 256 and 259 mm. The growth of largemouth bass was 104, 194, 271, 316, 350, 405 and 416 mm …
Development And Validation Test Of A Mule Deer Habitat Rule, Glenn Gephart
Development And Validation Test Of A Mule Deer Habitat Rule, Glenn Gephart
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
A mathematical description of Rocky Mountain mule deer (Odocoileus hemionus hemionus) habitat was developed and subjected to validation testing using correlation and multiple regression statistical techniques. Data were collected on a central Utah study area, which was divided into mountain and desert regions.
Data on deer utilization and several habitat components from 86 study plots visited in 1976 were used to develop a habitat rule. Data from 46 study plots visited in 1977 were used to test the accuracy of the rule. Deer utilization was determined from pellet group counts on 20 0.001 ha pellet plots at each …
Turbidity - Suspended Sediment Relations In A Subalpine Watershed, Thomas A. Holstrom
Turbidity - Suspended Sediment Relations In A Subalpine Watershed, Thomas A. Holstrom
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The effect of particle size distribution of suspended sediment vii upon a turbidity reading at a known concentration has been relatively quantified for stream bank materials on the Moccasin Basin - North Fork Fish Creek (MB-NFFC) Watershed, located in northwestern Wyoming. As expected, an increase in the median particle size in suspension results in a decrease of turbidity at a given concentration. The relationship derived correlates the particle size distribution of a chemically dispersed stream-bank material sample, with the Coefficient of Fineness for a mechanically dispersed portion of the sample.
Information Transfer And Regulation In A Model Ecosystem With Environmental Stochasticity, M. Mckee
Information Transfer And Regulation In A Model Ecosystem With Environmental Stochasticity, M. Mckee
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
The concept of regulation in ecosystems has been given considerable attention in the ecological literature, but no formal treatment has been offered. This study proposes a rigorous definition of regulation which is derived from the mathematics of information and communication theory. A theoretical, mathematical equivalent of the definition is also offered which implies serious limitations as to the value of most traditional laboratory population studies and deterministic population models in understanding regulation in ecosystems. The empirical validity of this theoretical equivalence is tested through use of a competition model of two diatoms. Other observations concerning the relationship between environmental variability …
Two Basic Methodological Choices In Wildland Vegetation Inventories: Their Consequences And Implications, Donald Alan Shute
Two Basic Methodological Choices In Wildland Vegetation Inventories: Their Consequences And Implications, Donald Alan Shute
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
In designing inventories of wildland vegetation, two of the many basic methodological choices are: 1) whether data are collected, reduced, and stored in discrete classes or as continuous variables, and 2) whether data are gathered as general purpose variables to bear upon many questions, or as specific purpose variables optimized for only one type of prediction. The effects of these two choices on accuracy of vegetation inventories to predict plant community production were examined by comparing regression models built upon differing sets of independent variables "inventoried" from a common data base. Contrary to expectations, discrete variables of classified community types …
Effects Of Forage Availability On Voluntary Intake And Feeding Behavior Of Grazing Heifers, Anastasios S. Nastis
Effects Of Forage Availability On Voluntary Intake And Feeding Behavior Of Grazing Heifers, Anastasios S. Nastis
All Graduate Theses and Dissertations, Spring 1920 to Summer 2023
Forage intake by animals is an important factor in determining production of livestock products from rangelands. However, relatively little is known of effects of such forage variables as availability and distribution in space upon intake. Even less is known about how the grazing animal modifies its feeding tactics when confronted with diminishing or limited supplies of available forage and how such altered behavior may affect the animal's energetic cost for existence. Forage intake, body weight gain, grazing time and biting rate of Angus heifers was related to forage availability and plant height on semiarid crested wheatgrass rangeland during the late …