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Articles 291721 - 291750 of 302428

Full-Text Articles in Physical Sciences and Mathematics

Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline May 1973

Bromegrass Productivity In Relation To Precipitation, Shrub Canopy Cover And Soil Nitrogen Content, Lawrence G. Kline

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

In seasons of above normal precipitation, populations of annual weedy species increase in great abundance in semi-arid desert plant communities. These increases in biomass tie up a considerable portion of the available nitrogen of such ecosystems and may depress subsequent annual grass germination.

A big sagebrush-annual bromegrass plant community was irrigated to simulate a spring growth period of abundant precipitation amenable to annual bromegras s productivity. Productivity and nitrogen content parameters were monitored throughout the spring and summer to evaluate the short and potential long term effects of this seasonal increase in "precipitation".

Irrigation increased annual bromegrass productivity almost 50 …


Petrology And Regional Relationships Of The Ordovician Kinnikinic Formation And Equivalents, Central And Southern Idaho, William Calvin James May 1973

Petrology And Regional Relationships Of The Ordovician Kinnikinic Formation And Equivalents, Central And Southern Idaho, William Calvin James

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The Kinnikinic Formation of central Idaho is a sedimentary unit consisting principally of orthoquartzite. From its maximum measured thickness of 2285 feet in the central Lemhi Range near Gilmore, Idaho, it thins westward to 376 feet at the type section and southward to 326 feet near Arco, Idaho. Northeast of the Lemhi Range it occurs only as erosional remnants, due to pre-Devonian erosion. Both the lower and upper contacts of the Kinnikinic Formation are disconformable.

The Kinnikinic Formation is light colored, predominately fine to medium grained, thin to medium bedded, and largely cemented by silica overgrowths. Some metamorphic recrystallization has …


Field Measurements Of Photosynthesis And Leaf Growth Rates Of Three Alpine Plant Species, Douglas A. Johnson May 1973

Field Measurements Of Photosynthesis And Leaf Growth Rates Of Three Alpine Plant Species, Douglas A. Johnson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Leaf photosynthetic measurements using a portable 14Co2 field system were carried out and correlative leaf relative growth rates, RGR, were determined at different leaf positions of three alpine plant species throughout the growing season. Initially there was a period of high leaf RGR associated with a period of increasing photosynthetic activity. Following this stage was a long period of no net change in length of the living leaf. During this period, photosynthetic activity generally increased to a maximum level and then decreased steadily. The final ontogenetic stage was a period of negative leaf RGR denoting leaf senescence which …


Mechanisms Of Population Regulation In Confined Colonies Of Peromyscus Maniculatus (Wagner) And The Response To Exploitation, Donna Corn Olsen May 1973

Mechanisms Of Population Regulation In Confined Colonies Of Peromyscus Maniculatus (Wagner) And The Response To Exploitation, Donna Corn Olsen

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Wild-trapped and laboratory-reared Peromyscus maniculatus (Wagner) were raised as confined colonies indoors with various stocking densities ranging from 0.026 to 0.100 mice per sq. ft. in pens of 40, 77, and 154 sq. ft. The animals were individually tagged and all pens were censused at weekly or semi-monthly intervals to record animals present, body weights, food consumption, and overt reproductive condition. At the termination of each experiment, all mice were necropsied and organ weights of gonads and adrenals recorded. Histological sections were made of the testes and ovaries. Half the colonies were subjected to density-independent exploitation by removal of 50% …


The Relationship Of Climatic Factors To Grazing Activities Of Cows On Winter And Spring Ranges, Benton M. Smith May 1973

The Relationship Of Climatic Factors To Grazing Activities Of Cows On Winter And Spring Ranges, Benton M. Smith

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this research was to investigate the effects of climatic variations upon the daily activities of grazing cattle. The activities of individual cows on a partially seeded salt desert shrub range were observed and recorded during three grazing periods. Two of the periods were during consecutive winters and the other during the spring. Climatic variations during the second winter period were quantified and compared to changes in the daily activity patterns of the cattle.

Distinctly different daily routines of cattle activities were evident for the winter and spring seasons. In the spring, the cattle grazed, traveled, and drank …


Habitat Selection By Large Wild Ungulates And Some Aspects Of The Energy Flow In A Sub-Tropical African Savanna Woodland Ecosystem, Stanley M. Hirst May 1973

Habitat Selection By Large Wild Ungulates And Some Aspects Of The Energy Flow In A Sub-Tropical African Savanna Woodland Ecosystem, Stanley M. Hirst

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

A study of habitat selection by large wild ungulates was carried out on a 50 cm2 area in the sub-tropical Lowveld region of eastern Transvaal province, South Africa. Estimations were made of herbaceous forage net productivity and ungulate secondary productivity on the same area.

Fourteen vegetation types, varying in composition and structure from open savanna to dense woodland, were delineated by association analysis. Structural and vegetational characteristics which were considered to influence ungulate distribution were measured within each vegetation type.

The study area supported resident populations of seven ungulate species during the wet season; drv season densities were higher …


The Foods And Feeding Habits Of Botulism Intoxicated And Healthy Waterbirds On The Bear River Refuge, Utah With Emphasis On The American Avocet And Blacknecked Stilt, George W. Wilson May 1973

The Foods And Feeding Habits Of Botulism Intoxicated And Healthy Waterbirds On The Bear River Refuge, Utah With Emphasis On The American Avocet And Blacknecked Stilt, George W. Wilson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Primary objectives of this study were: (1) to compare the food habits of healthy and botulism intoxicated American avocets and blacknecked stilts for qualitative and quantitative differences, (2) to determine which invertebrates found in the tracts of intoxicated and healthy birds contained type C toxin, and (3) to explain apparent susceptibilities among different sexes, ages and species of birds.

Based on percent utilization and occurrence of food items in the esophagus, the diets of healthy and intoxicated birds were similar. However, intoxicated avocets consumed higher proportions of Gastropoda and intoxicated stilts more Hydrophilidae larvae than did healthy birds. Because of …


Analysis Of Case Histories By Markov Chains Using Juvenile Court Data Of State Of Utah, Soo-Hong Uh May 1973

Analysis Of Case Histories By Markov Chains Using Juvenile Court Data Of State Of Utah, Soo-Hong Uh

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

The purpose of this paper is to analyze juvenile court data using Markov Chains. A computer program was generalized with a single array orientation for analyzing realizations of a Markov Chain to the kth order within machine limitations. The data used in this paper were gathered by the Juvenile Court of the State of Utah for administrative purposes and limited to District II. The results from the paper, "Statistical Inference About Markov Chains" by Anderson and Goodman, were applied for testing hypotheses. The paper is divided into five chapters: introduction, statistical background, methodology, analysis and summary, conclusions.


A Relativistic One Pion Exchange Model Of Proton-Neutron Electron-Positron Pair Production, William A. Peterson May 1973

A Relativistic One Pion Exchange Model Of Proton-Neutron Electron-Positron Pair Production, William A. Peterson

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Proton-neutron electron-positron pair production cross sections are calculated in the framework of the pseudoscalar one-pion exchange model in a fully relativistic manner.

A computer program has been developed to evaluate invariants and Dirac traces for a given data point.

The sections for symmetric coplanar events for laboratory kinetic energies of 10 to 250 MeV were calculated for pair angles of 20° to 120°.

Frequency distributions were also calculated, at a laboratory energy of 200 MeV, using a random number generator to select data points. The frequency distributions are illustrated by curves.

It was noted that the inclusion of heavier bosons …


Mineral And Chemical Content Of The Deep-Water Sediment Sequences Of Bear Lake, Utah-Idaho, James C. Biesinger May 1973

Mineral And Chemical Content Of The Deep-Water Sediment Sequences Of Bear Lake, Utah-Idaho, James C. Biesinger

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Twenty-five piston cores 6 to 12 feet long were obtained from the deepwater sediments of Bear Lake, Utah-Idaho. Analyses of these cores revealed that the deep-water sediments of the lake are divided into two major sequences: a younger sequence rich in carbonate minerals, here called the carbonate sequence, and an older sequence rich in silicate minerals, referred to in this paper as the silt sequence. The carbonate sequence is composed of clay-sized quartz, aragonite, calcite, dolomite, montmorillonite, illite, kaolinite, chlorite, and amorphous material. The silt sequence consists of both silt- sized and claysized particles of quartz, calcite, dolomite, montmorillonite, illite, …


A Comparison Of Consumer's Surplus And Monopoly Revenue Estimates Of Recreational Value For Two Utah Waterfowl Marshes, C. Holden Brink May 1973

A Comparison Of Consumer's Surplus And Monopoly Revenue Estimates Of Recreational Value For Two Utah Waterfowl Marshes, C. Holden Brink

All Graduate Theses and Dissertations, Spring 1920 to Summer 2023

Demand curves were estimated for waterfowl hunting and nonconsumptive recreational use from use rate and variable expenditure data collected at the Bear River Migratory Bird Refuge and the Farmington Bay Waterfowl Management Area during fiscal 1969. Consumer's surplus and monopoly revenue estimates were then derived from the demand functions. Adjusted estimates of consumer's surplus for waterfowl hunting amounted to $7,260 per year at Bear River and $11,400 per year at Farmington Bay. For nonconsumptive recreation annual consumer's surplus was estimated to be $18,700 at Bear River and $3,760 at Farmington Bay. Monopoly revenue estimates were between one-half and one-fourth the …


Kinetic Properties Of Partially Purified Isocitrate Dehydrogenase, Devji Dedhia May 1973

Kinetic Properties Of Partially Purified Isocitrate Dehydrogenase, Devji Dedhia

Masters Theses & Specialist Projects

Within the past few years kinetic studies of NADP+- specific isocitrate dehydrogenase have been conducted extensively following isolation from bacteria, yeast and vertebrates. However, the kinetic properties of NADP+ - specific isocitrate dehydrogenase have not been adequately characterized in filamentous fungi. Therefore, the present study was undertaken to examine the kinetic behavior of partially purified NADP+ - specific isocitrate dehydrogenase enzyme isolated from Phycomyces blakesleeanus.

During this study Michaelis constants (Km) and maximum velocities (Vmax) were determined for threo-Ds-isocitrate, NADP+, and Mn2+ as well as the number of binding sites of these …


Glacial Geology Of The Western Catskills, James Totten Kirkland May 1973

Glacial Geology Of The Western Catskills, James Totten Kirkland

Graduate Dissertations and Theses

Ic0 flow directions on the glaciated Appalachian Plateau in central New York were from the Adirondack Hountains. This is demonstrated by both striae directions and erratic provena..-1ce studies. No evidence for more than one Wisconsin glaciation as suggested by Rich (1935) could be found. Theories for local glaciation during the decline and after the retreat of the Laurentide Ice Sheet were also unsubstantiated. The East and West Branches Delaware River had different styles of daglaciation. The West Branch is characterized by zones of stagnation. The length of a zone is controlled by relief of the valley and corresponds to that …


Spatial Variations In The Intra-Urban Response To A Noise Source, Wilbur David Conder May 1973

Spatial Variations In The Intra-Urban Response To A Noise Source, Wilbur David Conder

Dissertations and Theses

Most research on the urban sonic environment has been recent. One finding has been that physical noise exposure indices calibrate poorly with human noise response. The vagaries of human response to noise have given impetus to research to isolate the factors that differentiate human response to noise. The present thesis continues this research.

The thesis specifies human noise response to occur on three levels: awareness, annoyance, and complaint. The factors that structure each level of noise response are identified in the published Iiterature.

Noise awareness is a function of noise exposure. Noise annoyance is a function of noise exposure to …


Groundwater Levels In Nebraska, 1972, M.J. Ellis May 1973

Groundwater Levels In Nebraska, 1972, M.J. Ellis

Conservation and Survey Division

No abstract provided.


The Nursing Process And Its Relationship To The Quality Of Nursing Care, Arlene H. Johnson May 1973

The Nursing Process And Its Relationship To The Quality Of Nursing Care, Arlene H. Johnson

Loma Linda University Electronic Theses, Dissertations & Projects

The purpose of this study was to determine the effect of the systematic use of the nursing process on the quality of nursing care. Quality nursing care was defined as being achieved when the patient's nursing care needs are identified and plans made to assist the patient with these needs.

It was hypothesized that the quality of nursing care would be improved by the participation of the team leaders in a series of classes on the nursing process. This improvement in quality nursing care would be evidenced by a higher correlation between the patient's needs perceived by the nurse and …


Abstracts Of Papers Presented At The 85th Session Of The Iowa Academy Of Science, April 27-28, 1973, Iowa Academy Of Science Apr 1973

Abstracts Of Papers Presented At The 85th Session Of The Iowa Academy Of Science, April 27-28, 1973, Iowa Academy Of Science

Iowa Academy of Science Documents

Presentation abstracts from the annual meeting of the Iowa Academy of Science


85th Session Of The Iowa Academy Of Science, April 27-28, 1973, Iowa Academy Of Science Apr 1973

85th Session Of The Iowa Academy Of Science, April 27-28, 1973, Iowa Academy Of Science

Iowa Academy of Science Documents

No abstract provided.


A General Lr(K) Parser Building Algorithm, Thomas Joshua Sager Apr 1973

A General Lr(K) Parser Building Algorithm, Thomas Joshua Sager

Mathematics & Statistics ETDs

The problem is to find an efficient algorithm that, given the productions of a context-free grammar G, will discover whether G is LR(k) for given k and if it is build an efficient parser for G . The algorithm is given in Section 8. It is essentially a synthesis of the best parts of Knuth's and DeRemer's algorithms. On simple LR(k) grarranars it yields a result equivalent to DeRemer's algorithm, and like Knuth's algorithm it will work on all LR(k) grammars.


New Techniques In Precision Gamma Scanning: Application To Fast Breeder Reactor Fuel Pins, John R. Phillips Apr 1973

New Techniques In Precision Gamma Scanning: Application To Fast Breeder Reactor Fuel Pins, John R. Phillips

Chemistry and Chemical Biology ETDs

A new precision gamma scanning system is described. The system is designed for the thorough, detailed, nondestructive characterization of irradiated fast reactor fuel pins. Gamma scanning data are given for failed fuel pin , transfer mechanisms of fission products, quantitative isotopic scan­ning, and differential burnup profiles.

The system consists of a scanning mechanism for the precise positioning (±0.001 in.) of the irradiated fuel pin, high density tungsten alloy collimators for defining the volume segment from which the gamma-ray spectra are collected, a large high resolution an anticoincidence detector assembly for resolving complex gamma-ray spectra, and a computer con­trolled data acquisition …


The Synthesis Of Pyrimidines And Condensed Pyridazines As Potential Antimetabolites, Judith A. Wagner Apr 1973

The Synthesis Of Pyrimidines And Condensed Pyridazines As Potential Antimetabolites, Judith A. Wagner

Chemistry and Chemical Biology ETDs

Interest in the compounds described by this thesis was first aroused in the early 1930's when a research team began to investigate the mass poisonings of the population in Indonesia. The cause of the poisonings seemed to be the foodstuffs which the people made for themselves from the abundant coconut. Two products in particular, Bongkrek and Semaji, made from coconut presscakes and grated coconut, were apparently the source of the toxic substance. When made under improper conditions, the toxic principle developed in an otherwise harmless food product. A compound was finally isolated and established as the toxic principle by …


Quasi-Landau Spectrum Of A Hydrogen Like Atom In A High Magnetic Field, Anthony F. Starace Apr 1973

Quasi-Landau Spectrum Of A Hydrogen Like Atom In A High Magnetic Field, Anthony F. Starace

Anthony F. Starace Publications

A two dimensional semiclassical approximation is used to examine the σ polarization spectrum of a hydrogen like atom in a strong magnetic field. Resonances above the zero field ionization limit are found and their energy separations are computed over the region from the ionization limit to 40 ħωc above, where ωc is the cyclotron frequency, for magnetic fields of 10, 17, 25, 32, 40 and 47 kG. At the ionization limit the separation between resonances is found to be 1.500 ħωc, independent of magnetic field strength, which is in agreement with a separation of 1.5 ħω …


A Study Of Trace Metal Concentrations In Two Species Of Mytilus Along The Pacific Coast Of The United States., George Harry Fullas Apr 1973

A Study Of Trace Metal Concentrations In Two Species Of Mytilus Along The Pacific Coast Of The United States., George Harry Fullas

Earth and Planetary Sciences ETDs

An investigation of iron, zinc, copper, and cadmium concentrations in Mytilus californianus and Mytilus edulis was conducted on specimens collected along the west coast of the United States. Animals and sea water were collected at six different areas and analyzed using an Atomic Absorption Spectrophotometer. Trace metal concentrations in the animals were influenced by the collection conditions of age, species, temperature, pollution, and metal relationships. Younger animals, of both species, contained higher concentrations of all the metals. Larger, or older animals, contained the smallest metal concentrations. Copper concentrations in the animals were higher in sea water with high copper content. …


Solid Waste Disposal And Ocean Dumping, John William Sellers Apr 1973

Solid Waste Disposal And Ocean Dumping, John William Sellers

Marine Affairs Theses and Major Papers

A broad-scope overview of the solid waste disposal problem as intensified by legislation against ocean dumping of such wastes. Since the problem of increasing ocean pollution was partly solved by extensive restrictions on ocean dumping, wastes formerly disposed of in the oceans must now be disposed of by other methods. These alternative methods are discussed and cost estimates applied insofar as feasible; effects on the environment and on the conservation of natural resources are also discussed. Efforts should be directed to determine the level of solid waste disposal which would result in beneficial effects, or at the worst, in non-harmful …


A Field Study Of Selected Ecological Properties Of Boca Ciega Bay And Adjacent Gulf Of Mexico, Geo-Marine, Inc. Apr 1973

A Field Study Of Selected Ecological Properties Of Boca Ciega Bay And Adjacent Gulf Of Mexico, Geo-Marine, Inc.

Reports

This report describes a quantitative study of selected environmental parameters in a portion of Boca Ciega Bay and in the Gulf of Mexico adjacent to Johns Pass. The investigation included an analysis of hydrography and water quality during the period 14-20 February 1973. The objective of the study was to assess the present marine environment in order to judge the ecological feasibility of discharging tertiary treated sewage effluent into Boca Ciega Cay or secondary treated effluent into the Gulf of Mexico. The discharge would come from the proposed expansion of the South Cross Bayou sewage treatment plant.


Water Resources News, Volume 5, No. 4, April 1973 Apr 1973

Water Resources News, Volume 5, No. 4, April 1973

Water Current Newsletter

Nebraska and the National Water Commission Report
Summer Institutes Announced at the University of Nebraska
Interdisciplinary Water Resources Seminar
Advisory Committee Chairman Elected
Another Sewage Treatment Fund Delay!
Natural Resource Districts Called Landmark Legislation
Water Resources Council Director Resigns
Wetlands Preservation Policy
Congress Criticizes Bureau of Reclamation
West Virginia Dam Collapse Study
Drinking Water Standards
Expro '73
Combined Sewers Problem
EPA Issues New Application Form for Submission of Grant Programs
Symposium on Wastewater Effluent Limits


Evaluation Of An Experiment In Computer -Assisted Tutoring, Stephen L. Cunningham, Robert Fuller Apr 1973

Evaluation Of An Experiment In Computer -Assisted Tutoring, Stephen L. Cunningham, Robert Fuller

Robert G. Fuller Publications

It was made apparent from the presentations at the Conference of Computers in Undergraduate Science Education that very few Computer-Assisted Instructional (CAI) programs in physics attempt to evaluate the performance of computer- tutored students in comparison with a control group. In this note, we discuss an experiment in which 23 beginning physics students out of a class of 64 were given a computer-administered tutoring test in place of the regular review recitation session prior to an hour exam on relativity. The performance of the computer-tutored group on the exam was compared to the performance of the rest of the class.


Li-8 Magnetic Dipole-Moment, Richard C. Haskell, Leon Madansky Apr 1973

Li-8 Magnetic Dipole-Moment, Richard C. Haskell, Leon Madansky

All HMC Faculty Publications and Research

Polarized 8Li nuclei recoiling from the reaction 7Li(d, p)8Li were implanted in Au, Pd, and Pt foils, and the Knight-shifted values of the 8Li magnetic dipole moment in these metals were measured by a resonant depolarization technique. From measurements of the spinlattice relaxation times of 8Li implanted in Au, Pd, and Pt, the Knight shifts of 8Li in these metals were estimated. A corrected value for the magnetic dipole moment of 8Li was found to be μ(8Li)=(1.653 35±0.000 35)μN. Attempts were also made to measure the quadrupole couplings of 8Li in single crystals of Be and Mg. While the resonance …


Local Connectivity In Graphs, Donald W. Vanderjagt Apr 1973

Local Connectivity In Graphs, Donald W. Vanderjagt

Dissertations

No abstract provided.


Reactions Of N₂F₄ And Sf₆ With H₂ Induced By Co₂ Laser Pulses And By Electrical Discharge, John Leslie Lyman Apr 1973

Reactions Of N₂F₄ And Sf₆ With H₂ Induced By Co₂ Laser Pulses And By Electrical Discharge, John Leslie Lyman

Theses and Dissertations

A high power pulsed CO_2 laser was used to induce reactions in gas mixtures containing either N_2F_4 or SF_6. The rate of laser induced dissociation of N_2F_4 to NF_2 was as much as 1000 times faster than the thermal rate, and the rate law was of lower order than the thermal, bimolecular rate law. Explosion threshold and induction time data were obtained for butene stabilized mixtures of N_2F_4 and H_2. HF laser gain was observed during the first few microseconds of CO_2 laser pulse, but it was strongly quenched by the explosion. The laser driven reaction of SF_6 with H_2 …