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  • About
  • The Global ETD Search service is a free service for researchers to find electronic theses and dissertations. This service is provided by the Networked Digital Library of Theses and Dissertations.
    Our metadata is collected from universities around the world. If you manage a university/consortium/country archive and want to be added, details can be found on the NDLTD website.
191

The archaeology of the Little Colorado drainage area

McGregor, John C. (John Charles), 1905-1992 January 1931 (has links)
No description available.
192

The structural geology of the Foy Ridge area, Twin Buttes, Arizona

Burroughs, Richard L. January 1959 (has links)
Foy Ridge is located about twenty-six miles south-southwest of Tucson, Arizona, and about a mile north of the Twin Buttes mining district. The sediments of the Roy Ridge area range in age from Cambrian to Recent. Separation of the Paleozoic section into mappable units has been complicated by post-Permian metamorphism. This metamorphism has destroyed any fossils that were probably once present, although a few remains of a Devonian Cladopora reef have been recognized. The metamorphism has caused a recrystallization of the limestones and an alteration of the shales to hornfels with stringers of epidote. The result is a sequence of altered Paleozoic rocks closely resembling one another. Lateral compression acting in a northeast-southwest direction played the major role in the tectonic history of the Foy Ridge area. Foy Ridge is the inverted limb of a large fold overturned to the northeast. As the fold was being produced thrust faults and wrench faults formed in the limbs. These first faults were cut off by the Foy Ridge fault that formed in the southwest limb of a northwest plunging anticline. This anticline was thrust forward (southwest) and upward until it was pressed against the inverted limb (Foy Ridge) and the adjacent fold. A disharmonic fold probably formed in the normal limb of the major fold of which Foy Ridge is a part. Thrust faults in the disharmonic fold repeated the lower Paleozoic section on the southwest side of Foy Ridge. As compression continued the last major thrust of the area was produced. This was the Bolsa Overthrust, which probably originated in the core of the disharmonic fold. It cut across the inverted limb of the major fold and may have also cut across the crest of the northwest plunging anticline northeast of the Foy Ridge fault. Intrusive activity followed or accompanied the overthrusting and folding of the area. This was closely followed by post-intrusion normal faulting. The Twin Buttes, two prominent hills immediately east of the thesis area, are a southeastern extension of the northeastern limb of the northwest plunging anticline that formed the hanging wall of the Foy Ridge fault. The "breached anticline" of the Twin Buttes mining district is probably related to the normal limb of the fold that formed Foy Ridge. The synclinal area between these two folds is covered by alluvium.
193

Structural geology of the Safford Peak Area, Tucson Mountains, Pima County, Arizona

Imswiler, James Bruce, 1929- January 1959 (has links)
No description available.
194

THE PSYCHOLOGICAL EFFECTS OF CULTURAL MYTHS: MANIPULATING BELIEFS ABOUT THE AMERICAN OLD WEST.

MORGANSTERN, DONNA RAE. January 1987 (has links)
The purpose of this research was to explore how theme parks influence visitors' beliefs about the past and the emotional and attitudinal effects of such beliefs. It was based on the theory that theme parks in portraying an ideal past communicate cultural myths that have psychological impact and that faith in those myths influence current emotions and attitudes. The experiment took place at Old Tucson, an old west theme park and movie location. The independent variables were designed to manipulate subjects' beliefs about what was true in the actual old west, as well as their motivation to reaffirm old west myths. Before entering Old Tucson, subjects were given either "no cue" or a "famous movie location cue." Earlier findings indicated "no cue" allowed reaffirmation of old west myths, while the "movie location cue" caused decreased mythic beliefs. Subjects also received either a culture boost or threat before entry, in the form of a trivia quiz. The boost was intended to leave subjects unmotivated to reaffirm old west myths; the threat was intended to motivate them to seek myth-affirmation at Old Tucson. Upon exit, subjects were surveyed about personal mood, the old west, Old Tucson, and social attitudes and beliefs. No-cue (allowed affirmation), culture-threat (motivation) subjects expressed significantly greater belief in the myth of the old west than their movie-cue (prevented affirmation), culture-threat (motivation) counterparts. Subjects who expressed great belief in the old west had significantly higher optimism about the future than those with lower beliefs. Primary dependent measures included mood (anxiety, depression, hostility, positive affect, and sensation seeking) enjoyment of Old Tucson and desire to return dogmatism, authoritarianism, alienation, attitudes toward technology, death, politics and the environment. Enjoyment of Old Tucson, desire to return, dogmatism, and optimism were positively correlated with strength of old west beliefs among subjects motivated, and able, to reaffirm them.
195

BIONOMICS AND MANAGEMENT OF PEST MOSQUITOES AT THE AGRO-URBAN INTERFACE, SANTA CRUZ VALLEY, ARIZONA (B.T.I., BIOLOGICAL CONTROL, I.P.M., BACILLUS THURINGIENSIS).

KINGSLEY, KENNETH JAMES. January 1985 (has links)
The Santa Cruz valley in Arizona is a rapidly urbanizing area. Complaints by residents of the area about pest mosquitoes prompted the investigation of mosquito breeding sources and a search for management techniques that would reduce mosquito populations. Many types of mosquito breeding sites were found in the area, and eight species of mosquitoes were identified. The greatest source of mosquitoes was a 2400 hectare irrigated pecan orchard. The most numerous and annoying mosquitoes were Aedes vexans (Meigen) and Psorophora columbiae (Dyar and Knab). The orchard is irrigated ca. every two weeks from April through October by flooding level areas, called borders, between rows of trees. Mosquitoes hatched with every irrigation studied, from April through September, but reached annoying numbers from late April through mid-September. A. vexans was the dominant species in early spring and P. columbiae was dominant in summer. Highest populations were reached coincident with the summer rainy season in July and August. Tests were performed to determine the efficacy of Bacillus thuringiensis israelensis (B.t.i.) as an additive to irrigation water for control of mosquito larvae. The larvicidal material was effective at all concentrations from .586 to 2.344 l/ha and with all techniques used. The most cost-effective application technique was to use fertilizer tanks to drip a mixture of B.t.i. into irrigation water in ditches before the water ran into fields. The general rate of three parts larvicide per million parts irrigation water was found to be effective, especially when supplemented with a spray of one part larvicide to 64 parts water applied to the ends of borders two to three days following irrigation. An increase in larvicide concentration was found to be necessary during the peak of mosquito season. A successful management program was developed and applied for 1 year, during which no mosquito complaints were made by citizens, the population of mosquitoes in the orchard was reduced to a point where farm laborers were no longer annoyed, and farm managers were satisfied that the program was cost effective.
196

Planktonic dynamics as an indicator of water quality in Lake Mead.

Staker, Robert Dale,1945- January 1973 (has links)
The purpose of this investigation was to identify the zooplankton and phytoplankton found in Lake Mead, to quantify their presence, to elucidate some temporal and spatial patterns, and to investigate some of the planktonic responses to physical, chemical, and biological parameters. Phytoplankton and zooplankton population samples were collected from eight different sites at il depths at six times over an annual period. These samples were collected with a 6-liter Van Dorn sampler. Phytoplankton samples were preserved in Lugol's solution and the zooplankton were placed in formalin preservative. The 503 zooplankton population samples were scored in a ruled counting chamber using a stereomicroscope. Eighteen species of zooplankton were identified. The 274 phytoplankton samples were placed on Millipore filters and slides were prepared for examination with phase contrast microscopy. A total of at least 79 algae were found to comprise the phytoplankton flora. The zooplankton for the most part were rotifers, cladocerans, and copepods. Keratella, the principal rotifer, was found to be diacmic and Bosmina, Daphnia, the calanoid, cyclopoid, and nauplii copepods were monacmic. Spatial relationships across the reservoir indicate that Bosmina and cyclopoid copepods are water quality indicators. The late summer phytoplankton were mostly Cyanophyta with populations as large as 5 x 10⁶ cells/liter occurring in Boulder Basin. Winter samples contained mostly diatoms and cryptomonads, while the spring phytoplankton was mainly Chlorophyta. The early summer flora showed a mixture of Chrysophyta, Chlorophyta, and Cryptophyta. Biomass determinations were made from average cell volumes and population counts. The blue-green alga Oscillatoria had the greatest biomass during the late summer period. Bacillariophyta reached a volumetric peak in late winter and the Chlorophyta in spring. The Cryptophyta showed a peak in winter while the Chrysophyta, represented mostly by the presence of Dinobryon, showed greatest population sizes in early summer. The Euglenophyta and Pyrrophyta were relatively unimportant groups of the biomass, Weak nocturnal migrations were exhibited by Asplanchna sp., Keratella cochlearis, and Bosmina longirostris. This conclusion was derived from an analysis of variance of the diurnal data. The copepod groups showed no migration patterns. Since this study was performed when the lake was isothermal, it is inferred that migration is a phenomenon not influenced by temperature. A transect study in Boulder Basin during the winter showed that Daphnia, Asplanchna, Chydorus, and Polyarthra, and possibly calanoid copepods, appear to be littoral, and are found mostly in the Las Vegas Wash area. Phytoplankton counts showed evidence for decreases in Bacillariophyta, Chlorophyta, Cyanophyta, and Cryptophyta across the basin from the wash to the dam area. Pyrrophyta Chrysophyta, and Euglenophyta were not important in the phytoplankton flora at this season. Nygaard's and Pearsall's ratios and Palmer's pollution- tolerant algae indices were applied to the phytoplankton data. Results of the Nygaard and Pearsall ratios, the migration study, the transect study, and the population studies indicate that Boulder Basin is eutrophic.
197

A mathematical model of eutrophication in Lake Mead.

Slawson, Guenton Cyril,1949- January 1974 (has links)
A conceptual model of an aquatic ecosystem has been formulated. The formulation incorporates largely empirical deterministic relationships describing biological response to abiotic and biotic environmental parameters into a stochastic representation of birth and death events. The occurrence of these events may be described as a Poisson process. Mathematical system theory provides a methodology for organizing the available information on aquatic ecosystem processes into a coherent and logical structure. This organizational capability is demonstrated. The portion of the conceptual model describing primary productivity has been calibrated and tested on an independent data set. This model works well for the Lake Mead system but needs to be tested on other aquatic systems to evaluate its managerial utility. The modeling of the complex interactions of aquatic food web processes requires further investigation to define an acceptable set of model coefficients.
198

Selections from A Frontier Documentary: Mexican Tucson, 1821-1856

McCarty, Kieran January 1994 (has links)
No description available.
199

LONG-TERM MONITORING OF RIPARIAN/WETLAND AREAS.

Noon, Kevin Francis. January 1982 (has links)
No description available.
200

A CRITICAL ANALYSIS OF ONE OF TUCSON'S EARLY TWENTIETH CENTURY HOTELS, THE EL CONQUISTADOR (ARIZONA).

Ketchum, Barbara Joan. January 1985 (has links)
No description available.

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